Reading...
Play button
Play button
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;
187 Cards in this Set
- Front
- Back
|
Acid dissociation constant (Ka)
|
The equilibrium constant that measures the degree of dissociation for an acid under specific conditions.
Ka = [H+][A-]/[HA] |
|
|
Acid anhydride
|
An oxide that dissolves in water to form an acidic solution.
|
|
|
Acidic solution
|
An aqueous solution that contains more H+ ions that OH- ions. The pH of an acidic solution is less than 7 at 25C.
|
|
|
Adiabatic process
|
A process that occurs without the transfer of heat to or from the system.
|
|
|
Alcohols
|
Organic compounds of the general formula ROH.
|
|
|
Aldehydes
|
Organic compounds of the general formula RCHO.
|
|
|
Alkanes
|
Hydrocarbons with only single bonds. The general formula for alkanes is CnH2n+2.
|
|
|
Alkenes
|
Hydrocarbons with at least one carbon-carbon double bond. Their general formula is CnH2n.
|
|
|
Amines
|
Compounds of the general formula RNH2, R2NH, or R3N.
|
|
|
Amorphous solids
|
Solids that do not possess long-range order. Compare to crystals or crystalline solids.
|
|
|
Amphoteric species
|
A species capable of reacting either as an acid or as a base.
|
|
|
Anhydride
|
A compound obtained by the removal of water from another compound.
|
|
|
Aquoeus solution
|
A solution in which water is the solvent.
|
|
|
Aromatic compounds
|
Planar, cyclic organic compounds that are unusually stable because of the delocalization of (pi)electrons.
|
|
|
Arrhenius acid
|
A species that donates protons (H+)in an aqueous solution; e.g., HCl.
|
|
|
Arrhenius base
|
A species that gives off hydroxide ions (OH-)in an aqueous solution; e.g., NaOH
|
|
|
Atom
|
The most elementary form of an element; it cannot be further broken down by chemical means.
|
|
|
Atomic mass
|
The averaged mass of the atoms of an element, taking into account the relative abundance of the various isotopes in a naturally occurring substance. Also called the atomic weight.
|
|
|
Atomic mass units (amu)
|
A unit of mass defined as 1/12 the mass of a carbon-12 atom; approximately equal to the mass of one proton or one neutron.
|
|
|
Atomic number
|
The number of protons in a given element.
|
|
|
Atomic orbital
|
The region of space around the nucleus in an atom in which there is a high probability of finding the electron.
|
|
|
Atomic radius
|
The radius of an atom. The average distance between a nucleus and the outermost electron. Usually measured as one-half the distance between two nuclei of an element in its elemental form.
|
|
|
Aufbau principle
|
The principle that electrons fill energy levels in a given atom in order of increasing energy, completely filling one sublevel before beginning to fill the next.
|
|
|
Avogadro's principle
|
The law stating that under the same conditions of temperature and pressure, equal volumes of different gases will have the same number of molecules.
|
|
|
Azimuthal quantum number (l)
|
The second quantum number, denoting the sublevel or subshell in which an electron can be found. Reveals the shape of the orbital. This quantum number represents the orbital angular momentum of the motion of the electron about a point in space.
|
|
|
Balanced equation
|
An equation for a chemical reaction in which the number of atoms for each element in the reaction and the total charge are the same for the reactants and the products.
|
|
|
Brometer
|
An instrument for measuring atmospheric pressure.
|
|
|
Base dissociation constant(Kb)
|
The equilibrium constant that measures the degree of dissociation for a base under specific conditions. For a base BOH:
Kb+[B+][OH-]/[BOH] |
|
|
Basic anhydride
|
An oxide that dissolves in water to form a basic solution.
|
|
|
Basic solution
|
An aqueous solution that contains more OH- ions than H+ ions. The pH of a basic solution is greater than 7 at 25C.
|
|
|
Beta (B) particle
|
An electron produced and ejected from the nucleus during radioactive beta decay.
|
|
|
Binding energy
|
The energy required to break a nucleus apart into its constituent neutrons and protons.
|
|
|
Bohr model
|
The model of the hydrogen atom postulating that atoms are composed of electrons that assume certain circular orbits about a positive nucleus.
|
|
|
Boiling point
|
The temperature at which the vapor pressure of a liquid is equal to the surrounding pressure. The normal boiling point of any liquid is defined as temperature at which its vapor pressure is 1 atmosphere
|
|
|
Boiling-point elevation
|
The amount by which a given quantity of solute raises the boiling point of liquid; a colligative property.
|
|
|
Bond energy
|
The energy (enthalpy change) required to break a particular bond under given conditions.
|
|
|
Bronsted-Lowry acid
|
Proton donor, e.g., H3PO4.
|
|
|
Bronsted-Lowry base
|
Proton acceptor, e.g., OH-
|
|
|
Buffer
|
A solution containing a weak acid and its salt(or a weak base and its salt) which tends to resist changes in pH.
|
|
|
Buffer region
|
The region of a titration curve in which the concentration of a conjugate acid is approximately equal to that of the corresponding base. THe pH remains relatively constant when small amounts of H+ or OH- are added because of the combination of these ions with the buffer species already in solution.
|
|
|
Calorie(cal)
|
A unit of thermal energy (1 cal=4.184J).
|
|
|
Calorimeter
|
An apparatus used to measure the heat absorbed or released by a reaction.
|
|
|
Carbohydrated
|
A compound with the general formula Cn(H20)m.
|
|
|
Carbon dating
|
A technique for estimating the age of (ancient) objects by measuring the amount of radioactive cargbon-14 remaining.
|
|
|
Carbonyl group
|
C=O group found in aldehydes, ketones, etcetera. THe C=O bond is known as the carbonyl bond, and organic compounds containing this group are known as carbonyl compounds.
|
|
|
Catalysis
|
Increasing a reaction rate by adding a substance (the catalyst) not permanently changed by the reaction. The catalyst lowers the activation energy.
|
|
|
Celsius (C)
|
A temperature scale defined by having 0C equal to the freezing point of water and 100C equal to the boiling point of water; also the units of that scale. Otherwise known as the centigrade temperature scale. 0C=273.15K.
|
|
|
Chemical bond
|
The interaction between two atoms resulting from the overlap of electron orbitals, holding the two atoms together at a specific average distance from each other.
|
|
|
Chemical properties
|
Those proprties of a substance describing its reactivity.
|
|
|
Closed system
|
A system that can exchange energy but not matter with its surroundings.
|
|
|
Colligative properties
|
Those properties of solutions that depend only on the number of solute particles present but not on the nature of those particles. See Boiing-point elevation; Freezing-point depression; Vapor-pressure lowering.
|
|
|
Common ion effect
|
A shift in the equilibrium of a solution due to the addition of ions of a species already present in the reaction mixture.
|
|
|
Compound
|
A pure substance that can be decomposed to produce elements, other compounds, or both.
|
|
|
Concentration
|
The amount of solute per unit of solvent (denoted by square brackets),or the relative amount of one component in a mixture.
|
|
|
Conjugate acid-base pair
|
Bronsted-Lowry acid and base related by the transfer of a proton, e.g., H2CO3 and HCO3-.
|
|
|
Coordination complex
|
A compound in which a central metal atom or ion is bonded by coordinate covalent bonds to other atoms or groups.
|
|
|
Critical pressure
|
The vapor pressure at the critical temperature of a given substance.
|
|
|
Critical temperature
|
The highest temperature at which the liquid and vapor phases of a substance can coexist; above this temperature the substance does not liquefy at any pressure.
|
|
|
Crystal
|
A solid whole atoms, ions, or molecules are arranged in a regular three-dimensional lattice structure.
|
|
|
Cycloalkanes
|
Saturated cyclic compounds of the formula CnH2n.
|
|
|
d subshell
|
The subshells corresponding to the angular momentum quantum number l=2, found in the third and higher principal energy levels; each containing five orbitals.
|
|
|
Degenerate orbitals
|
Orbitals that possess equal energy.
|
|
|
Density (p)
|
A physical property of a substance, defined as the mass contained in a unit of volume.
|
|
|
Diamagnetic
|
A condition that arises when a substance has no unpaired electrons and is slightly repelled by a magnetic field.
|
|
|
Diffusion
|
The random motion of gas or solute particles across a concentration gradient, leading to uniform distribution of the gas or solute throughout the container.
|
|
|
Dipole-dipole interaction
|
The attractive force between two dipoles whose magnitude is dependent on both the dipole moments and the distance between the two species.
|
|
|
Dipole moment
|
A vector quantity whose magnitude is dependent on the product of the charges and the distance between them. The direction of the moment is from the positive to the negative pole.
|
|
|
Dispersion force
|
A weak intermolecular force that arises from interactions between temporary and/or induced dipoles. Also called London force.
|
|
|
Dissolution
|
The process of dissolving a substance. The opposite of precipitation.
|
|
|
Dynamic equilibrium
|
A state of balance (no macroscopic change observable) that arises when opposing processes occur at equal rates.
|
|
|
Electrochemical cell
|
A cell within which a redox reaction takes place, containing two electrodes between which there is an electrical potential difference. See Electrolytic cell; Voltaic cell.
|
|
|
Electrolytic cell
|
An electrochemical cell that uses an external voltage source to drive a nonspontaneous redox reaction.
|
|
|
Electromagnetic radiation
|
A wave composed of electric and magnetic fields oscillating perpendicular to each other and to the direction of propagation.
|
|
|
Electromagnetic spectrum
|
The range of all possible frequencies or wavelengths of electromagnetic radiation.
|
|
|
Electromotive force (EMF)
|
The potential difference developed between the cathode and the anode of an electrochemical cell.
|
|
|
Electron (e-)
|
A subatomic particle that remains outside the nucleus and carries a single negative charge. In most cases its mass is considered to be negligible (1/1837 that of the proton).
|
|
|
Electron affinity
|
The amount of energy that is released when an electron is added to an atom.
|
|
|
Electron configuration
|
The symbolic representation used to described the electron occupancy of the various energy sublevels in a given atom.
|
|
|
Electron spin
|
The intrinsic angular momentum of an electron, having arbitrary values of +1/2 and -1/2. See Spin quantum number.
|
|
|
Element
|
A substance that cannot be further broken down by chemical means. All atoms of a given element have the same number of protons.
|
|
|
Emission spectrum
|
The spectrum produced by a species emitting energy as it relaxes from an excited to a lower energy state.
|
|
|
Empirical formula
|
The simplest whole number ratio of the different elements in a compound.
|
|
|
End point
|
The point in a titration at which the indicator changes color, showing that enough reactant has been added to the solution to complete the reaction.
|
|
|
Equilibrium
|
The state of balance in which the forward and reverse reaction rates are equal. In a system at equilibrium, the concentrations of all species will remain constant over time unless there is a change in the reaction conditions. See Le Chatelier's principle.
|
|
|
Equilibrium constant
|
The ratio of the concentration of the products to the concentration of the reactants for a certain reaction at equilibrium, all raised to their stoichiometric coefficients.
|
|
|
Equivalence point
|
The point in a titration at which the number of equivalents of the species being added to the solution is equal to the number of equivalents of the species being titrated.
|
|
|
Esters
|
Compounds of the general formula RCOOR'.
|
|
|
Ethers
|
Compounds of the general formula ROR'.
|
|
|
Excess reagent
|
In a chemical reaction, any reagent whose amount does not limit the amount of product that can be formed. Compare to Limiting Leagent.
|
|
|
f subshell
|
The subshells corresponding to the angular momentum quantum number l=3, found in the fourth and higher principal energy levels, each containing seven orbitals.
|
|
|
Faraday (F)
|
The total charge on 1 mole of electrons (1F= 96,487 coulombs).
|
|
|
Fatty acids
|
Carboxylic acids with long hydrocarbon chains, derived from the hydrolysis of fats.
|
|
|
First law of thermodynamics
|
The law stating that the total energy of a system and its surroundings remains constant. Also expressed as E=Q-W: the change in energy of a system is equal to the heat added to it minus the work done by it.
|
|
|
Formal charge
|
The conventional assignment of charges to individiual atoms of a Lewis formula for a molecule, used to keep track of valence electrons. Defined as the total number of valence electrons in the free atom minus the total number of nonbonding electrons minus one-half the total number of bonding electrons.
|
|
|
Freezing point
|
At a given pressure, the temperature at which the solid and liquid phases of a substance coexist in equilibrium.
|
|
|
Freezing-point depression
|
Amount by which a given quantity of solute lowers the freezing point of a liquid. A colligative property.
|
|
|
Galvanic cell
|
An electrochemical cell that uses a spontaneous redox reaction to do work, i.e., produce an electrical current. Also called a Voltaic cell.
|
|
|
Gamma radiation
|
High energy photons often emitted in radioactive decay.
|
|
|
Gas
|
The physical state of matter possessing a high degree of disorder, in which molecules interact only slightly; found at relatively low pressure and high temperatures. Also called vapor. See Ideal gas.
|
|
|
Gas constant (R)
|
A proportionality constant that appears in the ideal gas law, PV=nRT. Its value depends upon the units of pressure, temperature, and volume used in a given situation.
|
|
|
Geiger counter
|
An instrument used to measure radioactivity.
|
|
|
Gibbs free energy (G)
|
The energy of a system available to do work. The change in Gibbs free energy, G, is determined for a given reaction from the equation G=H-TS. G is used to predict the spontaneity of a reaction: A negative G denotes a spontaneous reaction, while positive G denotes a nonspontaneous reaction.
|
|
|
Graham's law
|
The law stating that the rate of effusion or diffusion of a gas is inversely proportional to the square root of the gas's molecular weight
|
|
|
Gram-equivalent weight
|
The amount of a compound that contains 1 mole of reacting capacity when fully dissociated. One GEW equals the molecular weight divided by the reactive capacity per formula unit.
|
|
|
Group
|
A vertical column of the periodic table, containing elements that are similar in their chemical properties.
|
|
|
Half-reaction
|
Either the reduction half or oxidation half of a redox reaction. Each half-reaction occurs at one electrode of an electrochemical cell.
|
|
|
Halogens
|
The active nonmetals in Group VIIA of the periodic table, which have high electronegativities and highly negative electron affinities.
|
|
|
Heat
|
The energy representing the kinetic energy of molecules that is transferred spontaneously from a warmer sample to a cooler sample. See Temperature.
|
|
|
Heat of formation (Hf)
|
The heat absorbed or released during the formation of a pure substance from the elements in their standard states.
|
|
|
Heat of fusion (Hfus)
|
The H for the conversion of a solid to a liquid.
|
|
|
Heat of sublimation (Hsub)
|
The H for the conversion of a solid directly to a gas.
|
|
|
Heat of vaporization (Hvap)
|
The H for the conversion of a liquid to a vapor.
|
|
|
Heisenberg uncertainty principle.
|
The principle that states that it is impossible to simultaneously determine with perfect accuracy both the momentum and position of a particle.
|
|
|
Henry's law
|
The law stating that the energy change in an overall reaction is equal to the sum of the energy changes in the individual reactions which comprise it.
|
|
|
Heterogeneous
|
Nonuniform in composition.
|
|
|
Homogeneous
|
Uniform in composition.
|
|
|
Hund's rule
|
The rule that electrons will occupy all degenerate orbitals in a subshell with single electrons having parallel spins before entering half-filled orbitals.
|
|
|
Hydridization
|
The combination of two or more atomic orbitals to form new orbitals for bonding purposes.
|
|
|
Hydrate
|
A compound with associated water molecules.
|
|
|
Hydrocarbons
|
Organic compounds containing only carbon and hydrogen.
|
|
|
Hydrogen bonding
|
The strong attraction between a hydrogen atom bonded to a highly electronegative atom, such as fluorine or oxygen, in one molecule, and highly electronegative atom in another molecule.
|
|
|
Hydronium ion
|
The H3O+ ion in aqueous solution.
|
|
|
Hydroxide ion
|
THe OH- ion
|
|
|
Ideal gas
|
A hypothetical gas whose behavior is described by the ideal gas law under all condition. An ideal gas would have particles of zero volume that do not exhibit interactive forces.
|
|
|
Ideal gas law
|
The law stating that PV=nRT, where R is the gas constant. It can be used to describe the behavior of many real gases at moderate pressures and temperatures significantly above absolute zero. See Kinetic molecular theory.
|
|
|
Indicator, acid-base
|
A substance used in low concentration during a titration that changes color over a certain pH range. The color changes, which occurs as the indicator undergoes a dissociation reaction, is used to identify the end point of the titration reaction.
|
|
|
Inert gases
|
The elements located in Group 0 (or Group VIII) of the Periodic Table. They contain a full octet of valence electrons in their outermost shell; this electron configuration makes them the least reactive of the elements. Also called Noble gases.
|
|
|
Intermolecular forces
|
The attractive and repulsive forces between molecules. See van der Waals forces.
|
|
|
Intramolecular forces
|
The attractive forces between atoms within a single molecules.
|
|
|
Ion
|
A charged atom or molecule that results from the loss or gain of electrons.
|
|
|
Ionic bonding
|
A chemical bond formed through electrostatic interaction between positive and negative ions.
|
|
|
Ionic solid
|
A solid consisting of positive and negative ions arranged into crystals that are made up of regularly repeated units and held together by ionic bonds.
|
|
|
Ionization product
|
The general term for the dissociation of salts or of weak acids or bases; the ratio of the concentration of the ionic products to the concentration of the reactant for a reaction, all raised to their stoichiometric coefficients.
|
|
|
Isobaric process
|
A process that occurs at constant pressure.
|
|
|
Isolated system
|
A system that can exchange neither matter nor energy with its surroundings.
|
|
|
Isothermal process
|
Process that occurs at constant temperature.
|
|
|
Joule (J)
|
A unit of energy; 1J=1Kg m2/s2
|
|
|
Kelvin (K)
|
A temperature scale with units equal in magnitude to the units of the Celsius scale and absolute zero defined as 0 K; also the units of that temperature scale. Otherwise known as the absolute temperature scale. 0K=-273.15 C.
|
|
|
Ketones
|
Compounds of the general formula RCOR'.
|
|
|
Kinetic energy
|
The energy a body has as a result of its motion, equal to 1/2mv2.
|
|
|
Kinetic molecular theory
|
The theory proposed to account for the observed behavior of gases. The theory considers gas molecules to be pointlike, volumeless particles, exhibiting no intermolecular forces and in constant random motion, undergoing only completely elastic collisions with the container or other molecules. See Ideal Gas Law.
|
|
|
Law of conservation of mass
|
The law stating that in a given reaction, the mass of the products is equal to the mass of the reactants.
|
|
|
Law of constant composition
|
The law stating that the elements in a pure compound are found in specific weight ratios.
|
|
|
Lewis acid
|
A species capable of accepting an electron pair; e.g., BF3-.
|
|
|
Lewis base
|
A species capable of donating an electron pair; e.e., NH3-.
|
|
|
Lewis structure
|
A method of representing the shared and unshared electrons of an atom, molecule, or ion.
|
|
|
Limiting reagent
|
In a chemical reaction, the reactant present in such quantity as to limit the amount of product that can be formed.
|
|
|
Liquid
|
The state of matter in which intermolecular attractions are intermediate between those in gases and in solids, distinguished from the gas phase by having a definite volume and from the solid phase in that the molecules may mix freely.
|
|
|
Litmus
|
An organic substance that is used as an acid-base indicator, most often in paper form. It turns red in acidic solution and blue in basic solution.
|
|
|
London force
|
See Dispension force.
|
|
|
Magnetic quantum number (ml)
|
The third quantum number, defining the particular orbital of a subshell in which an electron resides. It conveys information about the orientation of the orbital in space. (e.g., Px versus Py)
|
|
|
Manometer
|
An instrument used to measure the pressure of a gas.
|
|
|
Mass
|
A physical property representing the amount of matter in a given sample.
|
|
|
Mass defect
|
The difference between the sum of the masses of neutrons and protons forming a nucleus and the mass of that nucleus; the mass equivalence of binding energy, with the two related via the equation E=mc2.
|
|
|
Mass number
|
The total number of protons and neutrons in a nucleus.
|
|
|
Maxwell-Boltzmann distribution
|
The distribution of the molecular speeds of gas particles at a given temperature.
|
|
|
Melting point
|
The temperature at which the solid and liquid phases of a substance coexist in equilibrium.
|
|
|
Metallic bonding
|
The type of bonding in which the valence electrons of metal atoms are delocalized throughout the metallic lattice.
|
|
|
Metalloid
|
An element possessing properties intermediated between those of a metal and those of a nonmetal. Also called a semimetal.
|
|
|
Micelles
|
Clusters of molecules possessing hydrophilic ionic heads facing the surface of a sphere where they can interact with water, and possessing hydrophobic hydrocarbon tails in the interior. Soaps form micelles, facilitating the dissolution of oils and fats.
|
|
|
Miscible
|
Able to mix in any proportion.
|
|
|
Molality (m)
|
A concentration unit equal to the number of moles of solute per kilogram of solvent.
|
|
|
Molarity (M)
|
A concentration unit equal to the number of moles of solute per liter of solution.
|
|
|
Molar mass
|
The mass in grams of 1 mole of an element or compound.
|
|
|
Mole (mol)
|
One mole of a substance contains Avogadro's number of molecules or atoms. The mass of 1 mole of substance in grams is the same as the mass of one molecule or atom in atomic mass units.
|
|
|
Mole fraction (x)
|
A unit of concentration equal to the ratio of the number of moles of a particular component to the total number of moles for all species in the system.
|
|
|
Molecular formula
|
A formula showing the actual number and identity of all atoms in each molecules of a compound.
|
|
|
Molecular weight
|
The sum of the atomic weights of all the atoms in a molecules.
|
|
|
Molecule
|
The smallest polyatomic unit of an element or compound that exists with distinct chemical and physical properties.
|
|
|
Monoprotic acid
|
An acid that can donate only one proton, e.g., HNO3.The molarity of a monoprotic acid solution is equal to its normality.
|
|
|
Monosaccharides
|
Simple sugars that cannot be hydrolyzed to simpler compounds.
|
|
|
Net ionic equation
|
A reaction equation showing only the species actually participating in the reaction.
|
|
|
Nucleon
|
A particle found in the nucleus of an atom; can be either a neutron or a proton.
|
|
|
Neutralization reaction
|
A reaction between an acid and base in which H+ ions and OH- ions combine to produce water and a salt solution.
|
|
|
Neutral solution
|
An aqueous solution in which the concentration of H+ and OH- ions are equal (pH=7).
|
|
|
Neutron
|
A subatomic particle contained within the nucleus of an atom. It carries no charge and has a mass very slightly larger than that of a proton.
|
|
|
Noble gases
|
See Inert gases.
|
|
|
Nonmetal
|
One of a class of elements with high ionization potentials and very negative electron affinities that generally gains electrons to form anions. Nonmetals are located on the upper right side of the Periodic Table.
|
|
|
Nonpolar molecule
|
A molecule which exhibits no net separation of charge, and therefore no net dipole moment.
|
|
|
Normality(N)
|
A concentration unit equal to the number of gram equivalent weights of solute per liter of solution.
|
|
|
Nucleus
|
The small central region of an atom; a dense, positively charged area containing protons and neutrons.
|
|
|
Octet
|
Eight valence electrons in a subshell around a nucleus.
|
|
|
Octet rule
|
A rule stating that bonded atoms tend to undergo reactions that will produce a complete octet of valence electrons. Applies without exception only to C,N,O, and F with zero or negative formal charges.
|
|
|
Open system
|
A system that can exchange both energy and matter with its surroundings.
|
|
|
Orbital
|
A region of electron density around an atom or molecule, containing no more than two electrons of opposite spin. See Atomic orbital.
|
|
|
Order of reaction
|
In a calculation of the rate law for a reaction, the sum of the exponents to which the concentrations of reactants must be raised.
|
|
|
Osmosis
|
The movement of a solvent or solute through a semipermeable membrane across its concentration r=gradient, i.e., from a container in which the concentration is high to a container in which the concentration is low.
|
