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366 Cards in this Set
- Front
- Back
daltons atomic theory
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1. all elements are composed of indivisible atoms
2. all atoms of a given element are identical 3. atoms of different elements are different 4. compounds are formed by the combination of atoms of different elements |
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jj thompson
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cathode ray- electrons with negative charge
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plum pudding
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electrons spread out- positively charged with mass evenly distributed
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rutherford
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gold foil- some alpha particles get deflected- atoms have a dense central core, called a nucelus, while the rest of the atom is empty space
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bohr atom
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dense nucleus with electrons found in surrounding circular orbits- electrons can move to different energy levels- also called planetary model- was not entirely supported
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wave-mechanical model
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atom has a dense, positively charge nucleus but the electrons, instead of beinng in definite, fixed orbits, had fixed amounts of energy moving in areas called orbitals
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orbital
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a region in which an electron of a particular amount of energy is most likey to be located
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masses of subatomic particles
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protons and nuetrons - 1amu
electrons- 1/1836 amu |
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what does each atom of a specific element need to contain
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the same number of protons as each other atom of that element
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atomic number
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the number of protons in the nucelus of an atom
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mass number
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the sum of the number of protons and neutrons in an atom
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isotopes
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atoms of the same element that have a different number of neutrons and different mass numbers
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C-12 isotope, what does 12 represent
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12 is the mass number
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how do youy calculate the number of neutrons in an isotope
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it is the difference between the atomic number of the atom and its mass number
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atomic mass
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average mass of all the isotopes in a sample of the element
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ground state
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when the electrons occupy the lowest availablee orbitals
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excited state
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when the electrons are subjected to stimuli such as heat, light,m or electricity, an electron may absorb energy and temproarily move to a higher energy level, which makes it in n unstable condition called an excited state
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what happens to energgy when an electron moves up/down an energy level
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up=gains energy
down=emits energy (always a specific amount of energy) |
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what does the energy look like that is emitted from electrons
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it comes in the form of infrared, ultraviolet, or visible light
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what does visible light emitted by electrons look like
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bright line spectra
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how does the bright line spectra help us to identify elements
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individual elements always have hte same lineson the bright line spectra
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what determines the chemical properties of an atom
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the arrangement of electrons- the number of electrons in the outer energy level of its atoms (aka the number of valence electrons)
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principal quantum number
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the same number as the number of the energy level that contains the electron
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sublevels
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s, p, d, f
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how many orbitals do the sublevels have?
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s- one
p- three (px, py, pz) d- 5 orbitals f- seven orbitals |
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shape of s orbital
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spherical shapes without sharp edges surrounding the nucelus
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shape of p orbital
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dumbbell shape at right angles
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max number of electrons in each prinicipal energy level
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1- 2
2- 8 3- 18 4- 32 |
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node
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where it is unlikely to find an electron
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hunds rule
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a single electron must be placed into each orbital of a given sublevel before any pairing takes place
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what comes before 3d
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4s
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what comes before 4d
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5s
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homogenous
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uniform throughout- can contain more than one type of particle but particles are evenly mixed
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heterogenous
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are made up pf parts with different chemical and physical properties that are not uniformly mixed or dispersed
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pure substance
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its composition is the same throughout the sample
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2 examples of pure substances
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elements and compounds
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elements
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substances that cannot be broken down or decomposed into simpler substances by chemical means
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compounds
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composed of two or more elements that are chemically combined in definite proportions by mass- is still the same composition throughout
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law of definite proportions
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types of atoms in a compound exist in a fixed ratio
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mixture
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combinations of two or more pure substances that can be separated by physical means
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how are mixtures different from compounds
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1. their composition is not deifnite or "fixed"; no ratio
2. can be separated by physical means 3. in a mixture, the parts contain their properties; do not in a compound (compound has its own properties) |
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what elements exist in nature as two identical atoms covalently vonded into a diatomic molecule
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Br, I, N, Cl, H, O, F
(BrINCLHOF) |
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qualitative info
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relates to things that cannot be counted or measured
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quantitative info
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deals with things that can either be counted or measured
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empirical formula
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the simplest integer tatio in which atoms combine to form a compound
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ionic formulas
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indicate the ratio of the ions in a comound
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molecules
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units formed by covalently bonded substances
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molecular formula
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a multiple of the emprical formula
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ions
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are not neutral-- are either negative or positive and the neg. and pos. attract each other and forms a ratio that produces a neutral compound
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polyatomic ion
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a group of atoms covalently bonded together, possessing a charge
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how do compounds form
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1. aatraction of oppositely charged ions
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hydrate
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when wwater from some ioniic solutions evaporates, the solute forms a crystal lattice that binds water within the structure and forms a compound
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what do the oxidation numbers correspond to
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the group number (group one- 1+)
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order of ions in a binary ionic compound
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the positive first, then the negative
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how to name binary ionic compounds
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ex. NaCl
take the first ion sodium change the 2nd ion's ending to ide chloride sodium chloride ex. MgS= magnisium sulfide |
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how to name other ionic ocompunds
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if the metal is first, keep the name of the metal and the polyatomic ion
ex. KNO3= potassium nitrate if the neg. is a nonmetal, the ending is -ide ex. NH4Cl= ammonium chloride |
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binary covalent compound
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contains 2 metals
|
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how do you determine the order of compounds in a binary covalent compound
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electronegativity- the one with the lower electronegativity is written first
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how to name binary covalent compounds
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ends in ide, but uses prefixes to tell how many atoms of each element are present
ex. CO- carbon monoxide CO2- carbon dioxide N2O4- dinitrogen tetroxide |
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stock system
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used if a metal has more than one oxidation number
uses roman numerals to identify |
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physical changes
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changes that do not result in the formation of a new substance, but only change in appearance
ex. phase changes |
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chemical changes
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the identity of the products differs from the identity of the reactants
ex. bruning |
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endothermic
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processes that require energy in order to occur
S->L->G -lowers surrounding temp. bc energy is abosrbed from the surroundings -products have more potential energy than the reactants bc the reactants absorb energy as they become products H2O(s) + energy---> H2O(l) |
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exothermic
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-processes that release thermal energy when they occur
G->L->S -raises temp of surroundings bc energy is given off -products have less potential energy than the reactants x + y--> x + y + energy |
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law of conservation of mass
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matter is neither created nor detroyed in chemical reactions- must be balanced
|
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the 4 major types of reactions
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1. synthesis (combination)
2. decomposition (analysis) 3. single replacement reactions 4. double replacement reactions |
|
synthesis reactions
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combination
-when 2 or more reactants combine to form a product A+B--> AB |
|
decomposition
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-analysis
-reverse of synthesis -a single compund is broken down (decomposed) into two or more simpler substances AB--> A + B |
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single replacement
|
where one element replaces another element in a compound
-always involves an element and a compound -metals replace metals A + BX --> B + AX |
|
how do you know if a metal will replace another metal in a single replacement reaction/ a nonmetal reaplace a nonmetal
|
table j- a metal higher opn the table will replace a metal lower on the table/ a nonmetal higher up is more reactive and will reaplace a nonmetal lower on the table
|
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double replacement reactions
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generally involve two soluble ionic compounds that react in solution to produce a precipitate, a gas, or a molecular compound such as water
AB + CD --> AD + CB |
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3 ways you know if a double replacement reaction will occur
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1. one product is a solid
2. one product is a gas 3. a molecular substance like water is formed |
|
what is the masss of an atom in AMU relatively based on
|
the mass of a carbon-12 atom (amu- 12)
|
|
formula mass
|
the sum of the atmic masses of all the atoms present (the number of atoms of each elemnt mutiplied by the amu, then add all together)
|
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gram formula mass
|
in grams instead of amu
(also gram molecular mass if the elements form molecules) |
|
percentage composition
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the composition of a percentage of each element compared with the total mass of the compound
|
|
how to find percent composition
|
find the formula mass
divide the mass of the element you are trying to find by the formula mass, and mltiply by 100 |
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anhydrous
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srystals that contain attached water molecules
|
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avogadros number
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the number of particles in a mole of a substance
6.02 x 10^23 |
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mole
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the number of atoms of carbon pressent in 12 grams of c-12
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gram formula mass & moles
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the gram formula mass of any substance is the mass of one mole of that substance
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how to convvert grams to moles
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moles= number of grams x 1 mole
______ gram mass form |
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how to convert moles to grams
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grams= number of moles X
gram mass form _____________ 1 mole |
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solid phase
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-definite volume and shape
-rigid form -crystalline stucture |
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liquid phase
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-not as rigid as solid phase
-particles move past each other -no definite shape, but deifnite volume |
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gaseous phase
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-noo much attraction
-no definite volume or shape -spread out |
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fusion
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melting
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why does temp remain constant in heating and cooling curves even though heat is being added
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the heat is bsorbed in the form of potential energy- used to break bonds
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vaporization
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boiling
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on a curve, when are two phases present
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when the line is straight and temp is not increasing
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solidification
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freezing
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reverse opf boiling
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condensation
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sublimation
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solid changes directly to a gas
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deposition
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gas changes directly to a solid
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temperature
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measure of kinetic energy
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which way does heat flow
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from higher temp to the lower temp until the 2 are the same temp
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how to determine freezing and boiling points
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the freezing point/boiling ppoint of a substance is the equilibrium temperature of the two phases
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how to find kelvin
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celcius + 273
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calorimeter
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used to measure the amount of heat given off in a reaction
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heat of fusion
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the amount of heat needed to convert a unit mass of a substance from a solid to liquid at its melting point
|
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HEAT OF vaporization
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the amount of heat needed to convert a unit mass of a substance from its liquid phase to its vapor phase at constant temp
|
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kinetic molecular theory
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used to explain gases:
1. gases contain particles that are n constant, random, straight-line motion 2. gas particles collide with each other and with the wallsof the cnotain- energy is tranfered but not lost- elastic 3. gas partciles are separated- the volume occupied by the particles themselves is negligible 4. gas particles do not attract to eahc other |
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what happens to the pressure if more gas particles are added
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increase- directy proportional
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what happens to the pressure of a gas if you increae the volume
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pressure decreases- indirectly related
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temp and volume relationship of a gas
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as temp increases, volume increases
-directly related |
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temp and pressure relationship of a gas
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as temp increases, pressure increases
-directly related |
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relationship of temp and velocity of a gas
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as temp increases, velocity increases
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2 things about the knetic molecular theory that is not completely correct bc it talks about ideal gases
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1. gas particles do not attract each other- there is small attraction sometimes
2. gas particles do not occupy volume- as pressure increases the volume can no longer be ignored |
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what 2 gases are nearly ideal
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hydrogen and helium
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why do gases vary from ideal behavior
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1. increasing mass
2. increasing polarity |
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where as gases most ideal
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at low pressures and high temperatures
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what are a few ways the components of a mixture can be separated?
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density, molecular polarity, freezing point, and boiling point
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immiscible
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two liquids that are not soluble in each other
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filtration
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can separate the mixture of a solid in a liquid or se[arate solids and gases
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separatory funnel
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separates two liquids by density
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distillation
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can separate homogenous solutions of solids dissolved in liquids - separate by boiling points
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miscible
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when liquids mix with each other
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chromatography
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can separate mixtures
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what can be separated with a paper filter
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a solid in a liquid
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how is gasoline separated into its components
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fractional distillation
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what is the principal that allows paper chrmatography to separate mixtures
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components having differnet attractions to the paper
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how did mendeleev first putthe periodic table
|
in order of increasing atomic mass
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how is the periodic table now set up
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by increasing atomic number
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henry moseley
|
used x-rays to identify the atomic number of the elements
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periodic law
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the properties of the elements are periodic functions of their atomic numbers
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periods
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horizontal rows on the table
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what does the number at the beginning of hte period indicate
|
the principal energy level in which the valence electons are located
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properties in the period
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properties change across the period
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metalloids
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have some properties of metals and some of not metals
located 4 horizontal from group 13, with 2 in 14 and 2 in 15 |
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in what phase are metals and metalloidsa
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all solid except mercury
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what phases are nonmetals in
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all 3
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groups
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vertical columns
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what does each memeber of a given group contain, with a few exceptions
|
the same number of valence electrons, and therefore similar chemical properties
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where are the most active metals located
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in group 1 and 21
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how do metallic properties increase
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in any group, the metallic properties of the elements increase from the top to the bottom of the group
|
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what are some general properties of metals
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1. solid at room temp except mercury
2. most have densities greater than water, except group 1 3. malleable- can be hammered into shape 4. ductile 5. have luster 6. good conductors of heat and electricity bc of the mobility of their valence electrons 7. have low ionization energy and low electronegavity 8. tend to lose electrons to form positive ions with smaller radii |
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what is group 1 called
|
alkali metals
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transition elements
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group 3-group 12
typically hard solids with high melting points multiple oxidation states often forms ions that have color |
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properties of nonmetals
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1. many are gases or solids at room temp
2. not malleable or ductile- are brittle in solid phase 3. no luster- dull surface 4. high ionization energy and high electronegativity 5. poor conductors fo heat and electricity 6. tend to gain electrons to become negative ions with radii larger than their atoms |
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what is a element with more vvalence electrons most likely to do
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to gain electrons, forming a positive negative ion
|
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noble gases
|
the elements in group 18
-are genreally unreactive bc they have completely filled outer energy level, which makes them stable |
|
allotropes
|
some nonmetals can consist of two or more forms in the same phase
ex. O2 (oxygen) and O3 (ozone) |
|
how are allotropes different
|
different phsical and chemical proeprties
|
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where is the highest electronegavity on the table
|
top right
|
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ionization eergy
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the amount of energy needed to remove the most loosely bound electron from a neutral gaseous atom
|
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ionization energy and trends in a period
|
values increase across a period from left to right
|
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ionization trend in a group
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decreaes from top to bottom bc the valence electrons are at higher energy levels and are thus farther from the nucleus- it is easier to remove them when they are farther away
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atomic radius trends in a period
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from left to right, there is a repeating pattern of decreasing atomic radii (number of protons increase and pulls in electrons, causing decreasing atomic radius)
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atomic radius and groups
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atomic radius increases from top to bottom (more inner level electrons shield the valence electrons from the protons in the nucleus)
|
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ionic radius
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distance from hte nucleus to the outer energy level of the ion
-metallic ions are smaller bc it loses electrons when it becomes positive |
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electronegativity trends on the table
|
-highest electronegativity on the top of the group
-increases from left to right on the periods |
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what 3 groups have elements so reactive they cant be found in the free or uncombined state
|
groups 1, 2, and 17
|
|
propertie of hydrogen
|
-not in a group
-can form ionic compounds and covalent compounds |
|
what are elements in group 1 called
|
alkali metals
|
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what are the elements of group 2 called
|
alkaline earth metals
|
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properties of groups 1 and 2
|
easily lose their electrons
always found in compounds, not alone -low ionization and electronegativity |
|
when is the only time that oxygen has a positive oxidation value
|
when it vonds to the only element more electronegative than itself
|
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what is group 17 called
|
halogens
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halides
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when atoms of elements in group 17 gain an electron, they get a 1- charge and the salts formed are called halides
|
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what is the only group that has 3 states of matter at room temp
|
group 17- halogens
|
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what is the rule about electrons and boiling points in nonpolar mmolecules
|
more electrons= higher melting and boiling points
less electrons=lower melting points and boiling points |
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what element comes first when forming a compound
|
the only that loses the electrons comes first
|
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what kind of process is the breaking of a chemical bond
|
endothermic- energy is required to break a bond
|
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what kinwhat kind of process is the formation of a bond
|
exothermic- breaking a bond releases energy
|
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when a chemical bond is formed, does the formed compound have more or less potential energy than the substances from which is was formed
|
less potential energy bc energy is always released when a ond is formed
|
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stability vs. energy
|
the greater the energy released during the formation of a bond, the greater its stability
|
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kernel
|
the alll of an atoms nonvalence electrons
|
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atoms with a double bond
|
oxygen
|
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atoms with atriple bond
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nitrogen
|
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boiling and metal points of metals
|
high
|
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metallic bonding
|
results from the force of attraction of the mobile valence eletrons for an atom's positively charged kernel
|
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what term is used to describe metallic bonding and why
|
"sea of mobile electrons" - freedom of valence electrons
|
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where does metal bonding occu
|
between metal atoms that have vacant valence orbitals and low ionization energies
|
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crystalline lattice
|
metal
|
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octet
|
max number of valence electrons that an atom can have
|
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octet rule
|
atoms generally react by gaining, losing, or sharing electrons in order to get 8 valence electrons
|
|
covalent bond
|
formed when two nuclei share electrons in order to achieve a stable arrangement of electrons
-formed between two nonmetal atoms of the same element |
|
non polar covelent ond
|
attraction is equal- between two atoms of the same element - having equal or close electronegativity
|
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multiple covalent bond
|
when atoms share more than one pair of electrons (double and triple covalent bonds)
|
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polar bond
|
unequal sharing of electrons
|
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in a polar bond, which atom pulls harder
|
one with the high electronegativity
|
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in a polar bond, which atom has the pos. charge and which has the neg. charge
|
higher electronegativity attracts electrons more strongly, making that negative, and the lower electronegativity positive
|
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molecule
|
smallest discrete particle of an element or compound formed by covalently bonded atoms
|
|
properties of a molecule
|
soft, poor ocnductors of heat and electricity, and low melting and boiling pts
-can be solids, liquids, or gases |
|
what happens when metallic atoms react
|
1. lose electrons
2. become pos. charged ions 3. acquire a configuration that has a complete octet of electrons 4. their radii decrease |
|
what happens when nonmetallic atoms react
|
1. they gain electrons
2. they become negatively chared ions 3. they acquire a complete octet of electrons 4. their radii increase |
|
polarity and electronegativity
|
as the electronegativity difference between two atoms in a bond increases, the bond becomes more polar in nature
|
|
electronegativity and the type of bond
|
if the difference in electronegativity is -1.7 OR GREATER-, the bond is ionic
if the difference in electronegativity is less than that, it is covalent |
|
what do all compouns with polyatomic ions contain
|
both ionic and covalent bonds
|
|
melting and boiling pts of metallic, covalent, and ionic bonds
|
metallic- high
ionic- high covalent- low |
|
bonds and conductivity
|
metallic- good electrical and thermal conductivity
ionic- bad (unless melted) covalent- bad |
|
hardness of 3 bonds
|
ionic- hard
metallic- hard covalent- soft |
|
dipoles
|
polar molecules (bc they have positive and negative ends)
|
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when is the only time ionic molecules have good conductivity
|
in liquid and aqeuous states
|
|
dipole-dipole forces
|
when the positive area of one dipole molecule is attracted to the negative portion of an adjacent dipole molecule
|
|
hydrogen bond
|
an intermolecular bond between a hydrogen atom in one molecule and a nitrogen, oxygen, or fluorine atom in another molecule
|
|
where is hydrogen bonding specifically founbd
|
water
|
|
why does water have a high boiling pt.
|
hydrogen bonding- stronger than dipole-dipole attraction
|
|
why does hydrogen only bond with nitrogen, oxygen, and fluorine
|
they are highly electronegative and have small radii
|
|
solution
|
homogenous mixture of substances in the same physical state- can contain atoms, ions, or molecules of o
|
|
alloy
|
when metals are mixed to form a solution
|
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solute
|
the substance that is being dissolved; present in the smaller amount
|
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solvent
|
the substance that dissolves and is the greater amount
|
|
what is the most common solvent
|
water
|
|
properties of solutions
|
1. homogenous mixtures
2. clear and do not disperse light 3. have color 4. will not settle on stnading 5.will pass through a filter |
|
how does NaCl dissolve in water
|
pos. Na is attracted to the neg. part of the water and the neg. Cl is attracted to the pos. part of hte water
|
|
like dissolves like
|
yea- but ionic is insoluble in nonpolar solvent and soluble in polar solvent
|
|
temp and solubility
|
-as temp increases, most solids become more soluble in water
- as temp increases, the solubility of gases decrease |
|
pressure and solubility
|
pressure has little or no effect on the solubility of solid or liquid solutes
-incrases the solubility of gases in liquids (ex. soda can is oopened- press decreases and carbon dioxide escapes as bubbles bc it is no longer as soluble at thelowered press) |
|
if something is not soluble, what happens when it forms
|
it forms as a precipitate
|
|
howcan u tell if something is saturated
|
1. if the solution contains some undissolved solute
2. if you add a solute crystal and it dissolves, the orginial solution was unsatured; if it just falls to the bottom, it was saturated; if additinal crystals form, it was supersaturated |
|
molarity
|
the number of moles of solute in 1 L of solution
|
|
percent mass
|
mass of part
----------- x 100 mass of whole |
|
percent by volume
|
volume of solute
---------------- x 100 volume of solution |
|
what happens when u add salt to water
|
it lowers the freezing point of water
|
|
one mole of anything will lower the freezing point of water
|
true
|
|
why do ionic substances lower the freezing of water more than a molecular substance
|
bc when a molecular substance dissolves in water, oone mole of its particules is producted- ionic compounds break into ions so there are more moles
|
|
one mole of anytihng will raise the boiling pt of water
|
true
|
|
vapor
|
substance that is normally a solid or a liquid at room temp enters the gas phase
|
|
vapor pressure
|
as the temp of a liquid increases, the particles have more energy, and more particles escape from the surface- these vapor particles are gaseous particles and exert pressure in the gaseous phase
|
|
what does it mean if a gas exerts less vapor pressure
|
it has stronger intermolecular foces holding it in the liquid phase
|
|
when does a gas vaporize
|
when the vapor pressure equals the atmospheric pressrue
|
|
heatof vaporization
|
the heat required to change 1 mol ofa substance from a liquid at its boiling point to 1 mole of a vapor
|
|
what happpens to the boiling pt of water if you increase atmosperic pressure
|
the boiling pt increases
|
|
factors that affect rate of reaction
|
1. nature of the reactants
2. concentration 3. surface area 4. the presence of a catalyst 5. temp. |
|
nature of the reactants
|
covalent bonds are slower to react than ionic substance bc of the number of nods that must be broken- needs more energy
|
|
concentration
|
increase in concentration causes a faster rate bc there are more collisions
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surface area
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more surface area=more chances of collision=faster reaction rate
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catalyst
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substance that increaes the rate of a reaction by providing a different and easier pathapay for reaction
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temp
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increaes temp==faster molecules=more collisions and more energy=faster
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sum up of factors
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increasing all of them increaes the rate
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what must happen in order for a reaction to occur
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the reactants must have sufficient energy to collide effectively and they must be properly positioned
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activiated complex
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temporary, intermediate product thatmay either break apart and reform the reactants or rearrange th atoms and form new products
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on a potential energy diagram, what is any line that begins at the orgin of the y-axis
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a measure of PE
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activation energy
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the amount of energy needed to form the activated complex from the reatctants
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heat of reaction (delta H)
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the difference between the potential energy of the reactants and the potential energy of the products
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what do catalysts do to teh diagram
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lower the activiation energy
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endothermic diagram
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higher pe at the end
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exothermic diagram
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lower pe at the end
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equilibrium
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when both forward and reverse reactions occur at the same time- a state of balance between the rates of two opposite processes that are taking place at the same rate
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common misconceptation about equilibrium
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the products and reactants dont have to be equal, but the rates of the forward and reverse reactions have to be equal
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phase equilibrium
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melting points and freezing points- solid and liquid phases in closed and open containers
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solution equilibrium
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dissolving and recristalization are equal- equilibrium exists, solution is saturated
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le chateliers principle
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a system at equilibrium responds to relive stress on the system
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stress
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any change in temp, concentration, or pressure on an equilibrium system
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concentration changes
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if you increase one reactant, the other reactant will decrease and the products will increase- it will shift to the right
-if you decrease one reactant, the other reactant will increase and the products will decrease- shift to the left |
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temp changes
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if you raise the temp of one reactant, you raise the temp of the other and lower the temps of the two products and produce more heat (favors endothermic reaction)
-if you lower the temp of one reactant, you lower the temp of the other reactant, increae the temp of the products, and decrease the heat released (favors exothermic reaction) |
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pressure changes
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(does not affect rate of solids and liquids, but affects rate of gases)
-if pressure is added to the reacants, the system will shift to the right -if pressure is decreased from hte reacants, the system will shift to the left |
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what if both sides are gaseous
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an increase in pressure will favor the reaction toward the side with fewer gas molecules
-a decrease in pressure favors the reaction toward the side with the greater number of gas molecules |
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effect of a catalyst oon shifts
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changes reates equally- doesnt shift
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enthalpy
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tendency in nature to change to a state of lower energy
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entropy
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tendency in nature to change to a state of greater randomness or disorder- measure of the disorder or randness in a system- greater the disorder, higher the entropy
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examples of entropy
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physical changes (phase changes)
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equilibrium expression
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1. write a balanced equation for the system
2. place the products as factors in the numberator of the fraction and the reactants as factors in the denominator 3. place a square bracketaround each formula 4. write the coefficient of each substance as the power of its concentration |
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oxidation
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the loss of electrons by a atom or ion
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reduction
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the gain of electrons by an atom or ion
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redox
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combined name of oxidation and reduction, bc they cant occur alone
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LEO says GER
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loss of electrons- oxidation
gain of electrons- reduction |
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difference between ionic charges and oxidation numbers
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ion- 2+
oxidation- +2 |
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how to recognize a redox reaction
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1. uncombined element on one side, compound on the other
2. not redox if it is double replacement 3. if oxidation numbers change on hte other side |
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reducing agent
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gives electrons to reduce something else
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oxidizing agent
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accepts electrons from something else
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oxidized
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changes from lower oxidation number to a higher one
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reduction
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higher oxidation number ot a lower one
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electrochemical cell
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involves a chemical reaction and a flow of electrons
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two types of electrochemical cells
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1. voltaic cell- spontaenous chemical reaction produces a flow of electrons
2. electrolyic cells- requires an electric current to force a nonspontaneous chemical reaction to occur |
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electrode
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site at which oxidation or recuation occurs
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anode
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where oxidation occurs
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cathode
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where reduction occurs
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RED CAT/ AN OX
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reducation- cathode
oxidation- anode |
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salt bridge
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in a voltaic cell, connects the two containers and allows for the flow of ions, which makes a complete circuit and allows the reaction ot procede
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how do uknow which metal will be oxidized
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the metal higher on table J will be oxidized
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differences between voltaic and electrolytic
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1. voltaic is a battery, electrolytic uses a battery
2. voltaic= reduction is spontaenous, electrolyic is not 3. in voltaic the anode is neg and the cathode is pos in electrolytic the anode is pos and the cathode is neg. |
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electrolysis
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when electricity is used to force a chemical reaction to occur
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characteristics of an acid
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1. sour taste
2. aqueous solution conducts a current (strong acid=good conductor; weak acid=bad conductor) 3. svifd trsvy eiyh bases to form water and a salt 4. acids react with certain metals to produce hydrogen gas (metals about hydrogen on table j) 5. acids cause acid-base indicators to change color |
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neutralization
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double replacement reactions
acid+base--> salt + water |
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electrolytes
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substances that conduct a current
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solution electric current and ions
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more ions=better electrical conductivity
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characteristics of bases
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1. bitter taste
2. sliperry or soapy feeling 3. conduct electric current (strong base=more ions, more electricity) 4. react with acids to produce water and salt 5. cause acid-baes indicators to change color |
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Arrhenius acid
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a substance whose water solution contains the hydrogen ion as the only positive ion
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hydronium ion
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H3O formed when acids dissolve in water
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arrhenius base
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produces hydroxide (OH) ions when dissolved in water
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distinguishing bases from alcohols
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alcohols have carbon chains and CH chains
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naming binary acids
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hydro- followed by the name of the other element with an -ic ending _ acid
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ternary acids
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made of oxygen-containing polyatomic ions
ate->ic ic->ous |
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naming bases
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keep the name of the positive ion, and the name of the base ends with hydroxide
ex. Ca (OH)2 is calcium hydroxide |
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naming salts
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using the name of the positive ion of the base, and the negative ion of the aid
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what happens when metals reacts with an acid
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hydrogen gas and a salt are formed
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forming salts
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formed by strong acid and strong base= neutral
formed by strong acid and weak base= acidic |
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titration
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process of adding meaured volumes of an acid or a base of known concentration to an acid or a base of unknown concentration until netralization occurs
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arrhenius base
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produces hydroxide (OH) ions when dissolved in water
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distinguishing bases from alcohols
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alcohols have carbon chains and CH chains
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|
naming binary acids
|
hydro- followed by the name of the other element with an -ic ending _ acid
|
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ternary acids
|
made of oxygen-containing polyatomic ions
ate->ic ic->ous |
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naming bases
|
keep the name of the positive ion, and the name of the base ends with hydroxide
ex. Ca (OH)2 is calcium hydroxide |
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naming salts
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using the name of the positive ion of the base, and the negative ion of the aid
|
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what happens when metals reacts with an acid
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hydrogen gas and a salt are formed
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forming salts
|
formed by strong acid and strong base= neutral
formed by strong acid and weak base= acidic |
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titration
|
process of adding meaured volumes of an acid or a base of known concentration to an acid or a base of unknown concentration until netralization occurs
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how to solve titration
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Ma x Va= Mv x Vb
(molarity and volume of H+, " " of OH- |
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mono, di, and triprotic acids
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mono- H+ molarity=molarity of acid solution
di- H+ molarity=double the molarity of the acid solution tri- triple |
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mono and dihydroxy bases
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same thing as mono, di, and triprotic acids
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alkalinity
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how basic something is
|
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pH scale
|
-0-14
7 is neutral, under 7 is acidic, above 7 is basic -goes by tenfold- pH of 5 is 10 times more acidic than a pH of 6 (10 times more H+ ions) |
|
why does phenolphtalein turn pink when a base is adding
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phen. contains H+ that react with the base, phen. loses its hydrogen atom nad turns pink
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bronsted-lowry acid
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any substance that donates a hydrogen (H+) ion
-proton donor |
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bronsted-lowry base
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any substance that accept a proton (H+)
-proton accetor |
|
what makes a conjugate acid-base pair
|
they differ by a hydrogen ion
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salt
|
ionic substance composed of positively charged metallic or polyatomic ios, and negative ions other than hydroxide ions
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organic
|
carbon
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why can carbon form so many compounds
|
it forms chains, rings, and networks of compounds
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saturated organic compounds
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containing only single covalent bonds
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unsaturated organic compounds
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double or triple covalent bonds
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|
buckministerfullerence
|
buckyballl
-single bond to two carbon atoms and double bond to one carbon atom 60 carbon atoms, looks like a soccer ball |
|
homologous series
|
a group of related compounds in which each emmeber differs from the one before it by the same additional unit
|
|
hydrocarbons
|
organic compounds that contain only atoms of hydrogen and carvon
|
|
3 groups of hydrocarbons
|
alkanes, alkenes, and alkynes
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|
alkanes
|
a homologous series of saturated hydrocarbons that release energy when burned
-methane, ehtane, propane, butane |
|
formula for an alkane
|
(CnH2n+2)
times two, plus two |
|
wht happens to boiling pt as the number of carbons increases in an alkanes series
|
increases
|
|
alkene series
|
each member contains one double covalent bond between two carbons
|
|
formula for alkene
|
times two
(CnH2n) |
|
alkynes
|
homologous series of unsaturated hydrocarbons that contain one triple bond
|
|
formula for alkyne
|
CnH2n-2
times two, minus two |
|
isomer
|
when a molecular formula canbe represented by more than one structural arrangement
-have the same molecular formula but different chemical and physical properties |
|
how to name hydrocarbons that are not straight-chained
|
1. find the longest continuous chain of carbon atoms to name is propane, butane, etc.
2. find if there is a methyl, etc- if necessary, the location is shown with a number (ex 2-methyl) 3. if there are more than one alkyl group attacted, you can use di-, tri-, tetra- 4. if methyls are in different places, use numbers (ex. if there are two methyls o the second carbon and another on the third, it would be 2,2,3-trimethyl butane |
|
organic halide
|
halocarbon
when any halogens (F, Cl, Br, or I) replace hydrogen atoms in an alkane |
|
how to name an organic halide
|
by citing the location of the halogen attached to the chain
(ex. 2-fluropropane) |
|
alcohols
|
organic comoounds in which one or more hydrogen atoms of a hydrocarbon are replaced by an -OH group
|
|
what gives alcohols their properties
|
hydroxyl group - -OH group- functional group
|
|
is alcohol an electrolyte
|
no- does not form ions in water
|
|
primary, secondary, and tertiary alcohols
|
-based on whether the hydroxyl group is attached to a primary, secondary, or tertiary alcohol
(prim- R-OH sec- R-CH(OH)-R ter- R1R2R3COH |
|
monohydroxy, dihydroxy, trihydroxy alcohols
|
classified by the number of hydroxyl groups that are attached to the carbon chain
|
|
aldehydge
|
organic compounds in which the carbonyl group (C=O)is found on the end carbon
|
|
how do u name an aldehydge
|
place an -al instead of the final e of the alkane name
|
|
ketone
|
forned when the carbonyl group is found on an interior carbon atom that is attached to two other carbon atoms
|
|
how to name a ketone
|
replace the final -e with -one
|
|
organic acids
|
functional group is a carboxyl group (-COOH)
|
|
how to name an organic acid
|
replace -e with -oic
|
|
amino acid
|
contains -COOH but also an amine group (one of more hydrogen atoms replaced by an alkyl group)
|
|
combustion
|
burning
|
|
addition reactions
|
adding one or more atoms at a double or triple bond
|
|
substitution reaction
|
involves the replacement of one or more of the hydrogen atoms in a saturated hydrocarbon with another atom or group
|
|
esterification
|
reaction between an organic acid and an alcohol to produce an ester plus water
|
|
how to name alcohols
|
using the alkyl name of the alcohol plus the acid group with the end -oate
|
|
saponification
|
when an ester reacts with an inorganic base to produce an alcohol and a soap
|
|
fermentation
|
chemical process in which yeat cells secret enzume zymase and break the six-carbon chain of sugars into carbon diozide and alcohol
|
|
polymerization
|
the formation of large polymer molecules
|
|
addition polymerization
|
the joining of monomers (each individual unit of a polymer) of unsaturated compounds
|
|
transmutation
|
when the atomic nucelus of one element is changed into the nucelus of a different element
|
|
radioisotope
|
an isotope that is unstable and thus radioactive
|
|
alpha particle
|
helium with two protons and two neutrons
|
|
charge of alpha particle
|
2+
|
|
charge of positron
|
1+
|
|
penetrating power of the particles
|
aplha- low
beta and positron- moderate gamma- high |
|
charge of gamma
|
none
|
|
alpha decay
|
-atomic number decreases by two
-number of protons decreases by two -number of neutrons decreases by two -mass number decreases by four |
|
beta decay
|
-atomic number increaes by one
-number of protons increases by one -number of neutrons decreaes by one -mass number remains the same |
|
positron emission
|
-atomic number decreaes by one
-number of protons decreaes byone -number of neutrons increases by one -mass number remains the same |
|
difference between natural and aritifical transmuation
|
natural- single nucelus undergoing decay
aritiical- two reactants |
|
fission
|
splitting of a heavy nucelus to produce lighter nuclei
|
|
fusion
|
combing of light nuceli to produce a heavier nucelus
|
|
half life
|
the time it takes for half of the atoms in a given sample of an element to decay
|
|
c-14
|
known for dating previously living materials
|
|
U-238
|
radioactive through series until it is Pb-206- used to date rocks, etc
|
|
1-131, Cobalt 60
|
used for medical conditions
|