Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
96 Cards in this Set
- Front
- Back
indicators of physical changes
|
- change in visible appearance, not composition
- reversible or irreversible - ex: boil, melt, cut, bend, split, crack |
|
indicators of chemical changes
|
- energy is absorbed or released (temperature changes)
- color changes - gas production (bubbling, fizzing, odor change) - forms precipitate (solid that separates from solution and will not dissolve) - irreversibility (not easily reversible) |
|
heterogeneous mixtures
|
- not uniform in composition
- two or more phases |
|
homogeneous mixtures
|
- same composition throughout
- single phase |
|
extensive properties
|
- depend on amount of matter in sample
- mass, volume, calories |
|
intensive properties
|
- do not depend on amount of matter but type of matter
- hardness, density, BP |
|
physical changes
|
- changes in physical properties of a substance
- change in visible appearance without changing composition |
|
chemical changes
|
change where new form of matter is formed
|
|
physical properties
|
- observed without changing composition of the substance
- measured or observed with senses - color, odor, hardness, density, MP, BP, state, solubility, cutting, grinding |
|
chemical properties
|
- ability for substance to undergo chemical change
- after change, new substance is formed |
|
separation of mixtures
|
- some can be separated easily by physical means
- differences in physical properties can be used to separate mixtures - filtration – separates solid from liquid in a heterogeneous mixture (by size) - components of dyes such as ink may be separated by paper chromatography - distillation – takes advantage of different boiling points |
|
states of matter
|
solid, liquid, gas, plasma
|
|
solid
|
- matter that cannot flow
- definite shape and volume - fixed, closely packed arrangement of particles - particles cannot move from their spot, can move slightly back and forth (vibrate) |
|
liquid
|
- flows
- particles are free to move - definite volume, no definite shape but can conform to container - particles are packed closely together, but can move away from their spots (possibly packed closer than in a solid) |
|
gas
|
- no definite shape or volume
- particles spread apart, filling all the space available - particles can move around freely (more freely than liquid) - compressibility – either spread apart or squeezed together - have most energy in their particles |
|
plasma
|
- formed at high temperatures
- ionized phase of matter - very good conductor of electricity - affected by magnetic fields - indefinite shape, indefinite volume |
|
quantitative
|
- uses numbers to describe
- preferred by scientists because it is easier to check |
|
qualitative
|
- does not describe with numbers
- very descriptive - sometimes subjective |
|
scientific method
|
logical way of solving problems or answering questions
|
|
SI base units
|
- length – meter (m)
- mass – grams (g) - time – second (s) - temperature – Kelvin/Celsius (K/Cº) - energy – Joules (J) - volume – liters (L) - amount of substance – mole (mol) |
|
SI prefixes
|
.
|
|
SI derived units
|
- combination of SI units
- either multiply or divide units |
|
rules for significant figures and rounding
|
- all numbers other than zero
- which zeros count |
|
adding sig figs
|
.
|
|
subtracting sig figs
|
.
|
|
multiplying sig figs
|
.
|
|
dividing sig figs
|
.
|
|
metric conversions (i.e. grams –> kilograms)
|
.
|
|
dimensional analysis (i.e. converting ft to cm)
|
- mathematical technique that allows you to convert from one unit to another
|
|
density
|
the ratio of mass to volume, or mass divided by volume
|
|
accuracy
|
refers to the closeness of measurements to the correct or accepted value of the quantity measured
|
|
precision
|
refers to the closeness of a set of measurements if the same quantity made in the same way
|
|
molar mass
|
the mass of one mol of a pure substance
|
|
mass
|
amount of matter in an object
|
|
weight
|
gravitational pull on an object
|
|
structure of the atom
|
composed of two main regions: nucleus and electron cloud
|
|
Dalton's atomic theory and changes made to it
|
.
|
|
scientific discoveries of Thomson
|
identified electrons using cathode rays
|
|
scientific discoveries of Rutherford
|
- positively charged nucleus
- classified radiation |
|
scientific discoveries of Dalton
|
- atomic theory
|
|
scientific discoveries of Millikan
|
electron's charge
|
|
scientific discoveries of Bohr
|
model of the hydrogen atom
|
|
scientific discoveries of DeBroglie
|
wave particle duality of nature
|
|
atomic number
|
number of protons in the nucleus of each atom in a given element
|
|
mass number
|
protons + neutrons
|
|
isotopes
|
two or more atoms having the same atomic number (same number of protons) but different mass numbers (due to different number of neutrons)
|
|
two different types of notation for writing isotopes
|
- nuclear notation (ex: 235/92 Uranium)
- hyphen notation (ex: Uranium-235) |
|
law of multiple proportions
|
two or more elements can combine to form different compounds in whole number ratios
|
|
law of definite proportions
|
no matter how of any compound you have, its always the same proportions of elements
|
|
law of conservation of mass
|
states that mass is neither created nor destroyed during ordinary chemical reactions or physical changes
|
|
subatomic particles
|
- protons – positive particles in the nucleus
- neutrons – neutral particles in the nucleus - electrons – negative particles in the electron cloud |
|
nuclear forces
|
short range p+ and nº, p+ - p+ and nº - nº forces that hold nuclear particles together
|
|
Avogadro's number
|
- number of particles in one mole of a pure substance
- 1 mole = 6.022 x 10^23 |
|
Mole conversions (mol –> g, mol –> molecules, etc)
|
.
|
|
wavelength
|
distance between corresponding points on adjacent angles
|
|
frequency
|
number of waves that pass a given point in a specific time (usually one second)
|
|
electromagnetic spectrum
|
all forms of electromagnetic radiation
|
|
quanta
|
.
|
|
orbital
|
three-dimensional region around the nucleus that indicates the probable location of an electron
|
|
orbit
|
.
|
|
quantum numbers
|
they specify the properties of atomic orbitals and the properties of electrons in orbitals
|
|
quantum energy – step ladder from notes (order of sublevels and orbitals)
|
.
|
|
Heisenberg uncertainty principle
|
it is impossible to determine the position and velocity of an electron or any other particle (at the same time)
|
|
how atom reaches excited state, how it returns to ground state
|
- it reaches excited state from having a higher potential energy than its ground state
- it returns to ground state when it gives off the energy it gained - the energy it gives off is in the form of electromagnetic radiation |
|
list of all the sublevels in an atom, how many electrons can be in each sublevel
|
(see p. 105)
|
|
be able to write all three types of electron configuration – orbital, electron, noble gas
|
.
|
|
Aufbau principle
|
an electron occupies the lowest energy orbital that can receive it (wants to be very stable)
|
|
Hund's rule
|
orbitals of equal energy are each occupied by one electron before any orbital is occupied by a 2nd spin state
|
|
Pauli exclusion principle
|
no two electrons in the same atom can have the same set of four quantum numbers (each orbital can have a max of 2 electrons of opposite spin)
|
|
period trends – atomic radii
|
-
- |
|
period trends – ionic radii
|
-
- |
|
period trends – ionization energy
|
-
- |
|
period trend – electronegativity
|
-
- |
|
arrangement of modern periodic table
|
in order of increasing atomic number so that elements with similar properties fall in the same column or group
|
|
Moseley
|
his work led to both the modern definition of the atomic number and the recognition that the atomic number is the basis for organization of the periodic table
|
|
Mendeleev
|
created the first periodic table
|
|
horizontal rows
|
- called periods
|
|
vertical columns
|
- called groups
|
|
location, valence electrons, stability of metals and nonmetals
|
- valence electrons are located in the outermost s and p sublevels
- metals are less stable than nonmetals |
|
valence electrons
|
an electron that is available to be lost, gained, or shared in the formation of chemical compounds
|
|
properties of each group
|
.
|
|
lanthanides
|
.
|
|
actinides
|
.
|
|
group names
|
.
|
|
assigned elements
|
.
|
|
chemical bond
|
mutual attraction between nuclei and valence electrons of two atoms that binds them together
|
|
intermolecular forces
|
- forces of attraction between molecules
- vary in strength but are usually weaker than bonds |
|
ionic bonding
|
- when electrons are taken by one atom from another atom
|
|
covalent bonding
|
- when electrons are shared between two atoms
|
|
types of compounds formed using each bond
|
.
|
|
7 diatomic molecules
|
BrINClHOFs:
- Bromine - Iodine - Nitrogen - Chlorine - Hydrogen - Oxygen - Fluorine |
|
how polarity is determined
|
- by polarity of the bonds and shape of the molecule
|
|
resonance
|
refers to bonding in molecules that cannot be correctly represented by a single Lewis structure
|
|
polar covalent bonds
|
- covalent bond in which electrons are shared unequally
- |
|
nonpolar covalent bonds
|
- a covalent bond in which electrons are shared equally
- |
|
drawing Lewis structures
|
.
|