Term |
Definition |
Section of Book |
abbreviated electron configuration |
An electron configuration that uses one of the noble gases to represent the core of electrons up to that element |
Organization of Electrons in Atoms |
absolute zero |
The minimum possible temperature, labeled 0 K (zero kelvins) |
Other Units: Temperature and Density |
acid |
An ionic compound of the H+ cation dissolved in water |
Acids |
acid |
A compound that increases the amount of H+ ions in an aqueous solution |
Neutralization Reactions |
acid dissociation constant (Ka) |
The equilibrium constant for the dissociation of a weak acid into ions |
Some Special Types of Equilibria |
acid salt |
An ionic compound whose aqueous solution is slightly acidic |
Strong and Weak Acids and Bases and Their Salts |
activated complex |
See transition state |
Reaction Mechanisms |
activation energy (Ea) |
The minimum amount of kinetic energy molecules must possess for an effective collision to occur |
Factors that Affect the Rate of Reactions |
active site |
Area of enzymatic action where substrate molecules react |
Catalysis |
activity series |
A list of elements that will replace elements below them in single-replacement reactions |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
actual yield |
The amount that is actually produced in a chemical reaction |
Yields |
addition reaction |
A reaction where atoms are added across a double or triple bond |
Hydrocarbons |
adhesion |
The tendency of a substance to interact with other substances because of intermolecular forces |
Properties of Liquids |
adsorb |
Bind to the surface of another substance |
Catalysis |
alcohol |
An organic compound that contains an OH functional group |
Alkyl halides and alcohols |
aldehyde |
A compound that has a carbonyl functional group at the end of a chain of C atoms |
Other Oxygen-Containing Functional Groups |
aliphatic hydrocarbons |
A hydrocarbon based on chains of C atoms |
Hydrocarbons |
alkaline battery |
A type of dry cell that contains an alkaline (i.e., basic) moist paste, rather than an acidic paste |
Applications of Redox Reactions: Voltaic Cells |
alkane |
An aliphatic hydrocarbon with only single covalent bonds |
Hydrocarbons |
alkene |
An aliphatic hydrocarbon that contains a C–C double bond |
Hydrocarbons |
alkyl halide |
An organic compound that contains a halogen atom |
Alkyl halides and alcohols |
alkyne |
An aliphatic hydrocarbon that contains a C–C triple bond |
Hydrocarbons |
alpha particle |
A type of radioactive emission equivalent to a helium nucleus |
Radioactivity |
amide group |
A functional group that is the combination of the amine and carbonyl functional groups |
Other Functional Groups |
amide bond |
The bond between the N atom and the C atom in an amide. |
Other Functional Groups |
amine |
An organic derivative of ammonia |
Other Functional Groups |
amorphous solid |
A solid with no long-term structure or repetition |
Solids |
amphiprotic |
A substance that can act as a proton donor or a proton acceptor |
Brønsted-Lowry Acids and Bases |
analyte |
The reagent of unknown concentration |
Acid-Base Titrations |
angular momentum quantum number (ℓ) |
An index that affects the energy and the spatial distribution of an electron in an atom |
Quantum Numbers for Electrons |
anion |
A species with an overall negative charge |
Ions and Ionic Compounds |
anode |
The half cell that contains the oxidation reaction |
Applications of Redox Reactions: Voltaic Cells |
antibonding molecular orbital |
A higher energy molecular orbital generated by destructive combination of atomic orbitals |
Molecular Orbitals |
aromatic hydrocarbons |
Flat ring systems, which contain continuously overlapping p orbitals, such as benzene |
Hydrocarbons |
Arrhenius acid |
A compound that increases the hydrogen ion concentration in aqueous solution |
Arrhenius Acids and Bases |
Arrhenius base |
A compound that increases the hydroxide ion concentration in aqueous solution |
Arrhenius Acids and Bases |
atmosphere (atm) |
A unit of pressure equal to the average atmospheric pressure at sea level; defined as exactly 760 mmHg |
Pressure |
atom |
The smallest piece of an element that maintains the identity of that element |
Atomic Theory |
atomic mass |
The sum of the number of protons and neutrons in a nucleus |
Atomic Theory |
atomic mass |
The weighted average of the masses of the isotopes that compose an element |
Masses of Atoms and Molecules |
atomic mass unit |
One-twelfth of the mass of a carbon-12 atom |
Masses of Atoms and Molecules |
atomic number |
The number of protons in an atom |
Atomic Theory |
atomic radius |
An indication of the size of an atom |
Periodic Trends |
atomic symbol |
A one- or two-letter representation of the name of an element |
Atomic Theory |
atomic theory |
The concept that atoms play a fundamental role in chemistry |
Atomic Theory |
aufbau principle |
(German for “building up”): electrons fill the lowest energy orbitals first. |
Organization of Electrons in Atoms |
autoionization constant of water (Kw) |
The product of the hydrogen ion and hydroxide ion concentrations |
Autoionization of Water |
autoionization of water |
Water molecules act as acids (proton donors) and bases (proton acceptors) with each other to a tiny extent in all aqueous solutions |
Autoionization of Water |
Avogadro’s law |
A gas law that relates number of particles to volume |
Other Gas Laws |
balanced chemical equation |
A condition when the reactants and products of a chemical equation have the same number of atoms of all elements present |
The Chemical Equation |
base |
A compound that increases the amount of OH− ions in an aqueous solution |
Neutralization Reactions |
basic salt |
An ionic compound whose aqueous solution is slightly basic |
Strong and Weak Acids and Bases and Their Salts |
becquerel (Bq) |
A unit of radioactivity equal to 1 decay per second |
Units of Radioactivity |
beta particle |
A type of radioactive emission equivalent to an electron |
Radioactivity |
boiling (or vaporization) |
The process of a liquid becoming a gas |
Phase Transitions: Melting, Boiling and Subliming |
boiling point |
The characteristic temperature at which a liquid becomes a gas |
Phase Transitions: Melting, Boiling and Subliming |
boiling point elevation |
The increase of a solution’s boiling point because of the presence of solute |
Colligative Properties of Solutions |
boiling point elevation constant (Kb) |
The constant that relates the molality concentration of a solution and its boiling point change |
Colligative Properties of Solutions |
bond energy |
The approximate amount of energy needed to break a covalent bond |
Other Aspects of Covalent Bonding |
bond order |
A method of evaluating bond strength |
Molecular Orbitals |
bonding electron pair |
A pair of electrons that makes a covalent bond |
Covalent Bonds |
bonding molecular orbital |
The lower energy molecular orbital generated by constructive combination of atomic orbitals |
Molecular Orbitals |
Boyle’s law |
A gas law that relates pressure and volume at constant temperature and amount |
Gas Laws |
branched hydrocarbons |
A carbon compound that is not a straight chain, having substituents appended to the longest chain |
Branched Hydrocarbons |
Brønsted-Lowry acid |
Any species that can donate a proton to another molecule |
Brønsted-Lowry Acids and Bases |
Brønsted-Lowry base |
Any species that can accept a proton from another molecule |
Brønsted-Lowry Acids and Bases |
buffer |
A solution that resists dramatic changes in pH |
Buffers |
buffer capacity |
The amount of strong acid or base a buffer can counteract |
Buffers |
burette or buret |
A precisely calibrated volumetric delivery tube |
Acid-Base Titrations |
calorie |
A unit of energy measurement originally defined in terms of warming up a given quantity of water. 1 cal = 4.184 J |
Energy |
calorimeter |
A container used to measure the heat of a chemical reaction |
Enthalpy and Chemical Reactions |
calorimetry |
The process of measuring enthalpy changes for chemical reactions |
Enthalpy and Chemical Reactions |
capillary action |
The behavior of a liquid in narrow surfaces due to differences in adhesion and cohesion |
Properties of Liquids |
carbonyl group |
A functional group where an O atom and a C atom are joined with a double bond |
Other Oxygen-Containing Functional Groups |
carboxyl group |
A functional group composed of a carbonyl group and an OH group |
Other Oxygen-Containing Functional Groups |
carboxylate ion |
A negatively charged ion derived from a carboxylic acid |
Other Oxygen-Containing Functional Groups |
carboxylic acid |
A molecule with a carboxyl group |
Other Oxygen-Containing Functional Groups |
catalyst |
A substance that increases the speed of a reaction |
Shifting Equilibria: Le Chatelier’s Principle |
catalyst |
A substance thaty accelerates a reaction by participating in it without being consumed |
Factors that Affect the Rate of Reactions |
catalyst |
A substance that lowers the activation energy of a specific reaction by providing an alternate reaction pathway |
Catalysis |
cathode |
The half cell that contains the reduction reaction |
Applications of Redox Reactions: Voltaic Cells |
cation |
A species with an overall positive charge |
Ions and Ionic Compounds |
central atom |
The atom in the center of a molecule |
Covalent Bonds |
Charles’s law |
A gas law that relates volume and temperature at constant pressure and amount |
Gas Laws |
chemical bond |
The connection between two atoms in a molecule |
Molecules an Chemical Nomenclature |
chemical change |
The process of demonstrating a chemical property |
Some Basic Definitions |
chemical equation |
A concise way of representing a chemical reaction |
The Chemical Equation |
chemical equilibrium |
The point at which forward and reverse chemical reactions balance each other’s progress |
Chemical Equilibrium |
chemical nomenclature |
A very specific system for naming compounds, in which unique substances get unique names |
Molecules an Chemical Nomenclature |
chemical property |
A characteristic that describes how matter changes form in the presence of other matter |
Some Basic Definitions |
chemistry |
The study of the interactions of matter with other matter and with energy |
Introduction |
coefficient |
The part of a number in scientific notation that is multiplied by a power of 10 |
Expressing Numbers |
coefficient |
A number in a chemical equation indicating more than one molecule of the substance |
The Chemical Equation |
cohesion |
The tendency of a substance to interact with itself |
Properties of Liquids |
colligative property |
A property of solutions related to the fraction that the solute particles occupy in the solution, not their identity |
Colligative Properties of Solutions |
collision theory |
The theory that reactions occur when reactant molecules “effectively collide” |
Factors that Affect the Rate of Reactions |
combined gas law |
A gas law that combines pressure, volume, and temperature |
Other Gas Laws |
combustion reaction |
A chemical reaction in which a reactant combines with oxygen to produce oxides of all other elements as products |
Composition, Decomposition, and Combustion Reactions |
complete ionic equation |
A chemical equation in which the dissolved ionic compounds are written as separated ions |
Ionic Equations: A Closer Look |
composition reaction |
A chemical reaction in which a single substance is produced from multiple reactants |
Composition, Decomposition, and Combustion Reactions |
compound |
A combination of more than one element |
Some Basic Definitions |
compressibility factor |
A measure of the extent of deviation from ideal gas behaviour |
Real Gases |
concentrated solution |
A solution with a lot of solute |
Some Definitions |
concentration |
How much solute is dissolved in a given amount of solvent |
Some Definitions |
concentration (verb) |
The removal of solvent, which increases the concentration of the solute in the solution |
Dilutions and Concentrations |
condensation |
The process of a gas becoming a liquid |
Phase Transitions: Melting, Boiling and Subliming |
condensed structure |
A listing of the atoms bonded to each C atom in a chain |
Hydrocarbons |
conjugate acid-base pair |
Two species whose formulas differ by only a hydrogen ion |
Brønsted-Lowry Acids and Bases |
continuous spectrum |
An image that contains all colors of light |
Quantum Numbers for Electrons |
conversion factor |
A fraction that can be used to convert a quantity from one unit to another |
Converting Units |
covalent bond |
A chemical bond formed by two atoms sharing electrons |
Covalent Bonds |
covalent network solids |
A crystalline solid composed of atoms of one or more elements that are covalently bonded together in a seemingly never-ending fashion |
Solids |
critical point |
The point at the highest temperature and pressure at which liquids and gases remain distinguishable |
Properties of Liquids |
crystalline solid |
A solid with a regular, repeating three-dimensional structure |
Solids |
curie |
A unit of radioactivity equal to 3.7×1010 decays/s |
Units of Radioactivity |
d block |
The columns of the periodic table in which d subshells are being occupied |
Electronic Structure and the Periodic Table |
Dalton’s law of partial pressures |
The total pressure of a gas mixture, Ptot, is equal to the sum of the partial pressures of the components, Pi |
Gas Mixtures |
daughter isotope |
The product left over from the parent isotope in a nuclear equation |
Radioactivity |
decomposition reaction |
A chemical reaction in which a single substance becomes more than one substance |
Composition, Decomposition, and Combustion Reactions |
degrees |
The unit of temperature scales |
Other Units: Temperature and Density |
density |
A physical property defined as a substance’s mass divided by its volume |
Other Units: Temperature and Density |
deposition |
The process of a gas becoming a solid |
Phase Transitions: Melting, Boiling and Subliming |
derived unit |
A unit that is a product or a quotient of a fundamental unit |
Expressing Units |
diatomic molecule |
A molecule with only two atoms |
Molecules an Chemical Nomenclature |
diffusion |
The movement of gas molecules through one or more additional types of gas via random molecular motion |
Molecular Effusion and Diffusion |
dilute |
A solution with very little solute |
Some Definitions |
dilution |
The addition of solvent, which decreases the concentration of the solute in the solution |
Dilutions and Concentrations |
dilution equation |
The mathematical formula for calculating new concentrations or volumes when a solution is diluted or concentrated |
Dilutions and Concentrations |
dipole-dipole interactions |
An intermolecular force caused by molecules with a permanent dipole |
Intermolecular Forces |
dispersion force (or London dispersion force) |
An intermolecular force caused by the instantaneous position of an electron in a molecule |
Intermolecular Forces |
dissociation |
The process of an ionic compound separating into ions when it dissolves |
Ionic Equations: A Closer Look |
double bond |
A covalent bond composed of two pairs of bonding electrons |
Covalent Bonds |
double-replacement reaction |
A chemical reaction in which parts of two ionic compounds are exchanged |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
dry cell |
A modern battery that does not contain large amounts of aqueous solution |
Applications of Redox Reactions: Voltaic Cells |
dynamic equilibrium |
When a process still occurs but the opposite process also occurs at the same rate so that there is no net change in the system. |
Properties of Liquids |
effective nuclear charge (Zeff) |
The net nuclear charge feld by valence electrons |
Periodic Trends |
effusion |
The movement of gas molecules from one container to another via a tiny hole |
Molecular Effusion and Diffusion |
electrodes |
The cathode or anode of a voltaic cell |
Applications of Redox Reactions: Voltaic Cells |
electrolysis |
The process of making a nonspontaneous redox reaction occur by forcing electricity into a cell |
Electrolysis |
electrolytic cell |
A cell into which electricity is forced to make a nonspontaneous reaction occur |
Electrolysis |
electromagnetic spectrum |
The full span of the possible wavelengths, frequencies, and energies of light |
Light |
electron |
A tiny subatomic particle with a negative charge |
Atomic Theory |
electron affinity (EA) |
The energy change when a gas-phase atom accepts an electron |
Periodic Trends |
electron configuration |
A listing of the shell and subshells labels |
Organization of Electrons in Atoms |
electron deficient molecules |
A molecule with less than eight electrons in the valence shell of an atom |
Violations of the Octet Rule |
electron group geometry |
how electron groups (bonds and nonbonding electron pairs) are arranged |
Molecular Shapes and Polarity |
electron groups |
A covalent bond of any type or a lone electron pair |
Molecular Shapes and Polarity |
electron shell |
A term used to describe electrons with the same principal quantum number |
Quantum Numbers for Electrons |
electronegativity |
A scale for judging how much atoms of any element attract electrons |
Other Aspects of Covalent Bonding |
electroplating |
The deposition of a thin layer of metal on an object for protective or decorative purposes |
Electrolysis |
element |
A substance that cannot be broken down into simpler chemical substances by ordinary chemical means |
Some Basic Definitions |
elementary step |
Each event that occurs in a chemical reaction as a result of an effective collision |
Reaction Mechanisms |
elimination reaction |
The removal of a functional group (either X or OH) and a H atom from an adjacent carbon |
Alkyl halides and alcohols |
endothermic |
A chemical reaction that has a positive change in enthalpy |
Enthalpy and Chemical Reactions |
energy |
The ability to do work. is the ability to do work |
Energy |
enthalpy change |
The heat of a process at constant pressure; denoted ΔH |
Enthalpy and Chemical Reactions |
enthalpy of formation |
The enthalpy change for a formation reaction; denoted ΔHf. and is given the symbol ΔHf |
Formation Reactions |
enthalpy of fusion |
The amount of energy needed to change from a solid to a liquid or from a liquid to a solid |
Phase Transitions: Melting, Boiling and Subliming |
enthalpy of sublimation |
The amount of energy needed to change from a solid to a gas or from a gas to a solid |
Phase Transitions: Melting, Boiling and Subliming |
enthalpy of vaporization |
The amount of energy needed to change from a liquid to a gas or from a gas to a liquid |
Phase Transitions: Melting, Boiling and Subliming |
entropy |
The level of randomness (or disorder) of a system, or a measure of the energy dispersal of the molecules in the system |
Entropy and the Second Law of Thermodynamics |
enzyme |
Protein molecules which serve to catalyze biochemical reactions |
Catalysis |
enzyme-substrate complex |
The binding of substrate to the enzymatic active site |
Catalysis |
equilibrium constant (Keq) |
A numerical value that relates to the ratio of products and reactants at equilibrium |
The Equilibrium Constant |
equivalence point |
The point of the reaction when all the analyte has been reacted with the titrant |
Acid-Base Titrations |
ester group |
A functional group made by combining a carboxylic acid with an alcohol |
Other Oxygen-Containing Functional Groups |
ether group |
A functional group that has an O atom attached to two organic groups |
Other Oxygen-Containing Functional Groups |
evaporation |
The formation of a gas phase from a liquid at temperatures below the boiling point |
Properties of Liquids |
exact number |
A number from a defined relationship that technically has an infinite number of significant figures |
Converting Units |
exothermic |
A chemical reaction that has a negative change in enthalpy |
Enthalpy and Chemical Reactions |
expanded valence shell molecules |
A molecule with more than eight electrons in the valence shell of an atom |
Violations of the Octet Rule |
experiment |
A test of the natural universe to see if a guess (hypothesis) is correct |
Chemistry as a Science |
exponent |
The raised number to the right of a 10 indicating the number of factors of 10 in the original number |
Expressing Numbers |
f block |
The columns of the periodic table in which f subshells are being occupied |
Electronic Structure and the Periodic Table |
fission |
The breaking apart of an atomic nucleus into smaller nuclei |
Radioactivity |
formation reaction |
A chemical reaction that forms one mole of a substance from its constituent elements in their standard states |
Formation Reactions |
freezing point depression |
The decrease of a solution’s freezing point because of the presence of solute |
Colligative Properties of Solutions |
freezing point depression constant (Kf) |
The constant that relates the molality concentration of a solution and its freezing point change |
Colligative Properties of Solutions |
frequency |
The number of cycles of light that pass a given point in one second |
Light |
frequency factor (A) |
A factor that takes into account the frequency of reactions and the likelihood of correct molecular orientation |
Activation Energy and the Arrhenius Equation |
frontier molecular orbitals |
A term which refers to the HOMO and LUMO, the most likely orbitals to be involved in chemical reactions or processes |
Molecular Orbitals |
functional group |
A collection of atoms or bonds with certain characteristic reactions |
Alkyl halides and alcohols |
fundamental units |
One of the seven basic units of SI used in science |
Expressing Units |
gamma ray |
A type of radioactive emission that is a very energetic form of electromagnetic radiation |
Radioactivity |
gas law |
A simple mathematical formula that allows one to model, or predict, the behavior of a gas |
Gas Laws |
Gay-Lussac’s law |
A gas law that relates pressure with absolute temperature |
Other Gas Laws |
Geiger counter |
An electrical device that detects radioactivity |
Units of Radioactivity |
Gibbs free energy (G) |
A measure of spontaneity which incorporates both enthalpy and entropy |
Gibbs Free Energy |
Graham’s law of effusion |
A law which relates the rate of effusion of a gas to the inverse of the square root of its molar mass |
Molecular Effusion and Diffusion |
gray (Gy) |
A unit of radioactive exposure qual to 100 rad |
Units of Radioactivity |
half cell |
A part of a voltaic cell that contains one half reaction |
Applications of Redox Reactions: Voltaic Cells |
half reaction |
The individual oxidation or reduction reaction of a redox reaction |
Balancing Redox Reactions |
half reaction method |
The method of balancing redox reactions by writing and balancing the individual half reactions |
Balancing Redox Reactions |
half-life |
The amount of time it takes for one-half of a radioactive isotope to decay |
Half-Life |
half-life |
The amount of time required for the concentration of a reactant to drop to one half of its initial concentration |
Concentration-Time Relationships: Integrated Rate Laws |
heat |
The transfer of energy from one body to another due to a difference in temperature |
Work and Heat |
heating curve |
A plot of the temperature versus the amount of heat added |
Phase Transitions: Melting, Boiling and Subliming |
Hess’s law |
When chemical equations are combined algebraically, their enthalpies can be combined in exactly the same way |
Hess’s Law |
heterogeneous catalyst |
A catalyst that is in a different phase from one or more of the reactants |
Catalysis |
heterogeneous equilibrium |
An equilibrium in which more than one phase of reactants or products is present |
The Equilibrium Constant |
heterogeneous mixture |
A non-uniform combination of more than one substance |
Some Basic Definitions |
HOMO |
The highest occupied molecular orbital |
Molecular Orbitals |
homogeneous catalyst |
A catalyst that is present in the same phase as the reactant molecules |
Catalysis |
homogeneous mixture |
A uniform mixture of more than one substance that behaves as a single substance |
Some Basic Definitions |
Hund’s rule |
One electron is placed in each degenerate orbital before pairing electrons in the same orbital |
Organization of Electrons in Atoms |
hybridization |
A mathematical mixing of atomic orbitals |
Valence Bond Theory and Hybrid Orbitals |
hydrocarbons |
An organic compound composed of carbon and hydrogen |
Hydrocarbons |
hydrogen bonding |
The very strong interaction between molecules due to H atoms being bonded to N, O, or F atoms |
Intermolecular Forces |
hydrogenation reaction |
The reaction of hydrogen across a C–C double or triple bond, usually in the presence of a catalyst |
Hydrocarbons |
hydronium ion |
The actual chemical species that represents a hydrogen ion in aqueous solution |
Arrhenius Acids and Bases |
hypothesis |
An educated guess about how the natural universe works |
Chemistry as a Science |
hyrolysis |
A reaction with water |
Brønsted-Lowry Acids and Bases |
ICE chart |
A table used to calculate equilibria values featuring rows of initial, change and equlibria concentration |
Calculating Equilibrium Constant Values |
ideal gas |
A gas that conforms exactly to the tenets of the kinetic molecular theory |
Real Gases |
ideal gas law |
A gas law that relates all four independent physical properties of a gas under any conditions |
The Ideal Gas Law and Some Applications |
indicator |
A substance whose color change indicates the equivalence point of a titration |
Acid-Base Titrations |
initial rate |
The instantaneous rate at the start of a reaction |
Reaction Rates |
initial rates method |
A method to determine the rate law from the instantaneous reaction rate upon mixing the reactants |
Rate Laws |
instantaneous reaction rate |
The rate of reaction at one instant in time |
Reaction Rates |
intermediate |
A chemical species does not appear in the overall balanced equation and is generated in one elementary step but used up in a subsequent step |
Reaction Mechanisms |
ion |
A species with an overall electric charge |
Ions and Ionic Compounds |
ionic compound |
A compound formed from positive and negative ions |
Ions and Ionic Compounds |
ionic formula |
The chemical formula for an ionic compound |
Ions and Ionic Compounds |
ionic solid |
A crystalline solid composed of ions |
Solids |
ionization energy (IE) |
The amount of energy required to remove an elec tron from an atom in the gas phase |
Periodic Trends |
isolated system |
A system that does not allow a transfer of energy or matter into or out of the system |
Energy |
isomer |
A molecule with the same molecular formula as another molecule but a different structure |
Hydrocarbons |
isothermal |
A process that does not change the temperature |
Phase Transitions: Melting, Boiling and Subliming |
isotopes |
Atoms of the same element that have different numbers of neutrons |
Atomic Theory |
joule |
The SI unit of energy |
Energy |
Kelvin scale |
The fundamental unit of temperature in SI |
Other Units: Temperature and Density |
ketone |
A compound where the carbonyl carbon is attached to two carbon chains |
Other Oxygen-Containing Functional Groups |
kinetic energy |
The energy due to motion |
Kinetic-Molecular Theory of Gases |
kinetic-molecular theory of gases |
A model which helps us understand gases at the molecular level and their physical properties |
Kinetic-Molecular Theory of Gases |
kinetics |
The study of reaction rate and the factors that can influence reaction rate |
Introduction to Kinetics |
law of conservation of energy |
The total energy of an isolated system does not increase or decrease |
Energy |
law of mass action |
The relationship of the amounts of reactants and products at equilibrium |
The Equilibrium Constant |
Le Chatelier’s principle |
If an equilibrium is stressed, then the reaction shifts to reduce the stress |
Shifting Equilibria: Le Chatelier’s Principle |
Lewis diagram |
A representation of the valence electrons of an atom that uses dots around the symbol of the element |
Lewis Electron Dot Diagrams |
limiting reagent |
The reactant that runs out first for a given chemical reaction |
Limiting Reagents |
line spectrum |
An image that contains only certain colors of light |
Quantum Numbers for Electrons |
locant |
The numerical position of a substituent |
Branched Hydrocarbons |
lock and key model |
A simple model used to describe enzyme activity, where substrates must fit into appropriately shaped active sites |
Catalysis |
lone electron pairs |
A pair of electrons that does not make a covalent bond |
Covalent Bonds |
LUMO |
The lowest unoccupied molecular orbital |
Molecular Orbitals |
magnetic quantum number (ml) |
The index that determines the orientation of the electron’s spatial distribution |
Quantum Numbers for Electrons |
mass-mass calculation |
A calculation in which you start with a given mass of a substance and calculate the mass of another substance involved in the chemical equation |
Mole-Mass and Mass-Mass Calculations |
matter |
Anything that has mass and takes up space. is anything that has mass and takes up space |
Some Basic Definitions |
mean free path |
The average distance traveled by a molecule between collisions |
Molecular Effusion and Diffusion |
melting |
The process of a solid becoming a liquid |
Phase Transitions: Melting, Boiling and Subliming |
melting point |
The characteristic temperature at which a solid becomes a liquid |
Phase Transitions: Melting, Boiling and Subliming |
meniscus |
The curved surface a liquid makes as it approaches a solid barrier |
Properties of Liquids |
metal |
An element that conducts electricity and heat well and is shiny, silvery, solid, ductile, and malleable |
Some Basic Definitions |
metallic solid |
A solid with the characteristic properties of a metal |
Solids |
microstate (W) |
A term used to describe different possible arrangements of molecular position and kinetic energy, at a particular thermodynamic state |
Entropy and the Second Law of Thermodynamics |
millimeters of mercury (mmHg) |
The amount of pressure exerted by a column of mercury exactly 1 mm high |
Pressure |
mixture |
A physical combination of more than one substance |
Some Basic Definitions |
molality (m) |
The number of moles of solute per kilogram of solvent |
Quantitative Units of Concentration |
molar mass |
The mass of 1 mol of a substance in grams |
The Mole |
molar volume |
The volume of exactly 1 mol of a gas; equal to 22.4 L at STP |
The Ideal Gas Law and Some Applications |
molarity (M) |
The number of moles of solute divided by the number of liters of solution |
Quantitative Units of Concentration |
mole |
The number of things equal to the number of atoms in exactly 12 g of carbon-12; equals 6.022×1023 things |
The Mole |
mole fraction |
The ratio of the number of moles of a component in a mixture divided by the total number of moles in the sample |
Gas Mixtures |
mole fraction |
The ratio of the number of moles of a component to the total number of moles in a system |
Colligative Properties of Solutions |
molecular formula |
A formal listing of what and how many atoms are in a molecule |
Molecules an Chemical Nomenclature |
molecular geometry |
how the atoms in a molecule are arranged |
Molecular Shapes and Polarity |
molecular mass |
The sum of the masses of the atoms in a molecule |
Masses of Atoms and Molecules |
molecular orbital theory (MO theory) |
A more sophisticated model of chemical bonding where new molecular orbitals are generated using a mathematical process called Linear Combination of Atomic Orbitals (LCAO) |
Molecular Orbitals |
molecular polarity |
The vector sum of the individual bond dipoles |
Molecular Shapes and Polarity |
molecular solid |
A crystalline solid whose components are covalently bonded molecules |
Solids |
molecularity |
The total number of molecules that participate in the effective collision of the elementary step |
Reaction Mechanisms |
molecule |
The smallest part of a substance that has the physical and chemical properties of that substance |
Molecules an Chemical Nomenclature |
mole-mass calculation |
A calculation in which you start with a given number of moles of a substance and calculate the mass of another substance involved in the chemical equation, or vice versa |
Mole-Mass and Mass-Mass Calculations |
mole-mole calculation |
A stoichiometry calculation when one starts with moles of one substance and convert to moles of another substance using the balanced chemical equation |
The Mole in Chemical Reactions |
monomer |
The repeated unit of a polymer |
Polymers |
net ionic equation |
A chemical equation with the spectator ions removed |
Ionic Equations: A Closer Look |
neutral salt |
An ionic compound that does not affect the acidity of its aqueous solution |
Strong and Weak Acids and Bases and Their Salts |
neutralization reaction |
The reaction of an acid with a base to produce water and a salt |
Neutralization Reactions |
neutralization reaction |
The reaction of an acid and a base to produce water and a salt |
Arrhenius Acids and Bases |
neutron |
A subatomic particle with no charge |
Atomic Theory |
node (nodal plane) |
An area of zero electron density |
Molecular Orbitals |
nomenclature |
The rules of naming in organic chemistry |
Branched Hydrocarbons |
nonmetal |
An element that exists in various colors and phases, is brittle, and does not conduct electricity or heat well |
Some Basic Definitions |
nonpolar covalent bond |
The equal sharing of electrons in a covalent bond |
Other Aspects of Covalent Bonding |
normal boiling point |
The characteristic temperature at which a liquid becomes a gas when the surrounding pressure is exactly 1 atm |
Phase Transitions: Melting, Boiling and Subliming |
nuclear energy |
The controlled harvesting of energy from fission reactions |
Nuclear Energy |
nuclear equation |
A chemical equation that emphasizes changes in atomic nuclei |
Radioactivity |
nuclear model |
The model of an atom that has the protons and neutrons in a central nucleus with the electrons in orbit about the nucleus |
Atomic Theory |
nucleus |
The center of an atom that contains protons and neutrons |
Atomic Theory |
odd-electron molecules |
A molecule with an odd number of electrons in the valence shell of an atom |
Violations of the Octet Rule |
orbital |
The specific set of principal, angular momentum, and magnetic quantum numbers for an electron |
Quantum Numbers for Electrons |
osmosis |
The tendency of solvent molecules to pass through a semipermeable membrane due to concentration differences |
Colligative Properties of Solutions |
osmotic pressure |
The tendency of a solution to pass solvent through a semipermeable membrane due to concentration differences |
Colligative Properties of Solutions |
oxidation |
The loss of one or more electrons by an atom; an increase in oxidation number |
Oxidation-Reduction Reactions |
oxidation |
The loss of one or more electrons by an atom; an increase in oxidation number |
Oxidation-Reduction Reactions |
oxidation number |
A number assigned to an atom that helps keep track of the number of electrons on the atom |
Oxidation-Reduction Reactions |
oxidation number |
A number assigned to an atom that helps keep track of the number of electrons on the atom |
Oxidation-Reduction Reactions |
oxidation-reduction (redox) reactions |
A chemical reaction that involves the transfer of electrons |
Oxidation-Reduction Reactions |
p block |
The columns of the periodic table in which p subshells are being occupied |
Electronic Structure and the Periodic Table |
parent isotope |
The reactant in a nuclear equation |
Radioactivity |
parts per billion (ppb) |
Ratio of mass of solute to total mass of sample times 1,000,000,000 |
Quantitative Units of Concentration |
parts per million (ppm) |
Ratio of mass of solute to total mass of sample times 1,000,000 |
Quantitative Units of Concentration |
parts per thousand (ppth) |
Ratio of mass of solute to total mass of sample times 1,000 |
Quantitative Units of Concentration |
Pauli exclusion principle |
No two electrons in an atom can have the same set of four quantum numbers |
Organization of Electrons in Atoms |
percent yield |
Actual yield divided by theoretical yield times 100% to give a percentage between 0% and 100% |
Yields |
percentage composition by mass (or mass percentage, % m/m) |
Ratio of mass of solute to the total mass of a sample times 100 |
Quantitative Units of Concentration |
periodic table |
A chart of all the elements |
Atomic Theory |
periodic trends |
The variation of properties versus position on the periodic table |
Periodic Trends |
pH |
The negative logarithm of the hydrogen ion concentration |
The pH Scale |
pH scale |
The range of values from 0 to 14 that describes the acidity or basicity of a solution |
The pH Scale |
phase |
An important physical property that defines whether matter is a solid, liquid, gas or supercritical fluid |
Some Basic Definitions |
phase diagram |
A graphical representation of the equilibrium relationships that exist between the phases of a substance under specified pressures and temperatures |
Properties of Liquids |
photon |
The name of a discrete unit of light acting as a particle |
Light |
physical change |
A change that occurs when a sample of matter changes one or more of its physical properties |
Some Basic Definitions |
physical property |
A characteristic that describes matter as it exists |
Some Basic Definitions |
pi bond (π bond) |
The sideways overlap of p orbitals, placing electron density on opposite sides of the inter-nuclear axis – a double or triple bond |
Valence Bond Theory and Hybrid Orbitals |
Planck’s constant |
The proportionality constant between the frequency and the energy of light: 6.626 × 10−34 J·s |
Light |
pOH |
The negative logarithm of the hydroxide ion concentration |
The pH Scale |
polar covalent bond |
A covalent bond between different atoms that attract the shared electrons by different amounts and cause an imbalance of electron distribution |
Other Aspects of Covalent Bonding |
polarity |
A measure of the unequal sharing of electrons which has resulted in a dipole moment |
Other Aspects of Covalent Bonding |
polyatomic ions |
An ion that contains more than one atom |
Ions and Ionic Compounds |
polymer |
A long molecule made of many repeating units |
Polymers |
polymerization |
The process of making a polymer |
Polymers |
polyprotic acid |
An acid capable of donating more than one H+ ion |
Some Special Types of Equilibria |
precipitate |
A solid that falls out of solution in a precipitation reaction |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
precipitation reaction |
A chemical reaction in which two ionic compounds are dissolved in water and form a new ionic compound that does not dissolve |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
prefix |
A prefix used with a unit that refers to a multiple or fraction of a fundamental unit to make a more conveniently sized unit for a specific quantity |
Expressing Units |
pressure |
Force per unit area |
Pressure |
primary battery |
A battery that cannot be recharged |
Applications of Redox Reactions: Voltaic Cells |
principal quantum number (n) |
The index that largely determines the energy of an electron in an atom |
Quantum Numbers for Electrons |
product |
A final substance in a chemical equation |
The Chemical Equation |
proton |
A subatomic particle with a positive charge |
Atomic Theory |
qualitative |
A description of the quality of an object |
Chemistry as a Science |
quantitative |
A description of a specific amount of something |
Chemistry as a Science |
quantization |
When a quantity is restricted to having only certain values |
Quantum Numbers for Electrons |
quantum mechanics |
The theory of electrons that treats them as a wave |
Quantum Numbers for Electrons |
quantum number |
An index that corresponds to a property of an electron, like its energy |
Quantum Numbers for Electrons |
rad |
A unit of radioactive exposure equal to 0.01 J/g of tissue |
Units of Radioactivity |
radioactive decay |
The spontaneous change of a nucleus from one element to another |
Radioactivity |
radioactivity |
Emanations of particles and radiation from atomic nuclei |
Radioactivity |
Raoult’s law |
The mathematical formula for calculating the vapor pressure of a solution |
Colligative Properties of Solutions |
rate constant (k) |
A proportionality constant specific to each reaction at a particular temperature |
Rate Laws |
rate-determining step |
The slowest step in a multistep mechanism |
Reaction Mechanisms |
rate law |
A mathematical relationship between the reaction rate and the reactant concentrations |
Rate Laws |
reactant |
An initial substance in a chemical equation |
The Chemical Equation |
reaction mechanism |
The bond making and bond breaking steps which occur at the molecular level during a chemical reaction |
Reaction Mechanisms |
reaction order |
The sum of the concentration term exponents in a rate law equation |
Rate Laws |
reaction rate |
The speed of a chemical reaction |
Introduction to Kinetics |
real gases |
A gas that deviates from ideal behaviour |
Real Gases |
redox reaction |
A chemical reaction that involves the transfer of electrons |
Oxidation-Reduction Reactions |
reduction |
The gain of one or more electrons by an atom; a decrease in oxidation number |
Oxidation-Reduction Reactions |
reduction |
The gain of one or more electrons by an atom; a decrease in oxidation number |
Oxidation-Reduction Reactions |
rem |
A unit of radioactive exposure that includes a factor to account for the type of radioactivity |
Units of Radioactivity |
ribozyme |
Ribonucleic acid (RNA) molecules capable of catalyzing certain chemical reactions |
Catalysis |
root-mean-square (rms) speed (urms) |
The speed of molecules having exactly the same kinetic energy as the average kinetic energy of the sample |
Kinetic-Molecular Theory of Gases |
s block |
The columns of the periodic table in which s subshells are being occupied |
Electronic Structure and the Periodic Table |
salt |
Any ionic compound that is formed from a reaction between an acid and a base |
Neutralization Reactions |
salt |
Any ionic compound that is formed from a reaction between an acid and a base |
Arrhenius Acids and Bases |
salt bridge |
A part of a voltaic cell that contains a solution of some ionic compound whose ions migrate to either side of the voltaic cell to maintain the charge balance |
Applications of Redox Reactions: Voltaic Cells |
saturated hydrocarbons |
A carbon compound with the maximum possible number of H atoms in its formula |
Hydrocarbons |
saturated solution |
A solution with the maximum amount of solute dissolved in it |
Some Definitions |
science |
The process of knowing about the natural universe through observation and experiment |
Chemistry as a Science |
scientific law |
A specific statement that is thought to be never violated by the entire natural universe |
Chemistry as a Science |
scientific notation |
An expression of a number using powers of 10 |
Expressing Numbers |
screening |
The repelling valence electrons by core electrons |
Periodic Trends |
second law of thermodynamics |
A spontaneous process will increase the entropy of the universe |
Entropy and the Second Law of Thermodynamics |
secondary battery |
A battery that can be recharged |
Applications of Redox Reactions: Voltaic Cells |
semimetal |
An element that has properties of both metals and nonmetals |
Some Basic Definitions |
semipermeable membrane |
A thin membrane that will pass certain small molecules but not others |
Colligative Properties of Solutions |
SI unit |
International System of Units used by all scientists, literally translated from “le Système International d’unités.” |
Expressing Units |
Sievert (Sv) |
Sievert (Sv) is a related unit and is defined as 100 rem |
Units of Radioactivity |
sigma bond (σ bond) |
Orbital overlap to form a bond which has cylindrical symmetry – a single bond |
Valence Bond Theory and Hybrid Orbitals |
significant figures |
The limit of the number of places a measurement can be properly expressed with |
Significant Figures |
silicones |
A polymer based on a silicon and oxygen backbone |
Polymers |
single bond |
A covalent bond composed of one pair of electrons |
Covalent Bonds |
single-replacement reaction |
A chemical reaction in which one element is substituted for another element in a compound |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
solidification |
The process of a liquid becoming a solid |
Phase Transitions: Melting, Boiling and Subliming |
solubility |
The maximum amount of a solute that can be dissolved in a given amount of a solvent |
Some Definitions |
solubility rules |
General statements that predict which ionic compounds dissolve and which do not |
Types of Chemical Reactions: Single- and Double-Displacement Reactions |
solute |
The minor component of a solution |
Some Definitions |
solution |
See homogeneous mixture |
Some Basic Definitions |
solvent |
The major component of a solution |
Some Definitions |
specific heat capacity |
The proportionality constant between heat, mass, and temperature change; also called specific heat |
Work and Heat |
spectator ion |
An ion that does nothing in the overall course of a chemical reaction |
Ionic Equations: A Closer Look |
spin quantum number (ms) |
The index that indicates one of two spin states for an electron |
Quantum Numbers for Electrons |
spontaneous process |
A process that occurs without the influence of external forces or a change that moves a system towards equilibrium |
Spontaneous Change |
standard molar entropy (So) |
The entropy of 1 mole of a substance in its standard state, at 1 atm of pressure |
Measuring Entropy and Entropy Changes |
standard notation |
A straightforward expression of a number |
Expressing Numbers |
standard temperature and pressure (STP) |
A set of benchmark conditions used to compare other properties of gases; 100 kPa for pressure and 273 K for temperature |
The Ideal Gas Law and Some Applications |
stoichiometry |
The relating of one chemical substance to another using a balanced chemical reaction |
Stoichiometry |
strong acid |
Any acid that is 100% dissociated into ions in aqueous solution |
Strong and Weak Acids and Bases and Their Salts |
strong base |
Any base that is 100% dissociated into ions in aqueous solution |
Strong and Weak Acids and Bases and Their Salts |
sublimation |
The process of a solid becoming a gas |
Phase Transitions: Melting, Boiling and Subliming |
subshell |
A term used to describe electrons in a shell that have the same angular momentum quantum number |
Quantum Numbers for Electrons |
substance |
Matter that has the same physical and chemical properties throughout. |
Some Basic Definitions |
substituent |
A branch off a main chain in a hydrocarbon |
Branched Hydrocarbons |
substrate |
The reactants which are specific for a biological catalyst |
Catalysis |
supercritical fluid |
A phase beyond the critical point, where liquid and gas phases are no longer distinct |
Properties of Liquids |
supersaturated solution |
A unstable solution with more than the normal maximum amount of solute in it |
Some Definitions |
surface tension |
An effect caused by an imbalance of forces on the atoms at the surface of a liquid |
Properties of Liquids |
surrounding atoms |
An atom that makes covalent bonds to the central atom(s) |
Covalent Bonds |
system |
The part of the universe under study |
Energy |
temperature |
A measure of the average amount of kinetic energy a system contains |
Other Units: Temperature and Density |
theoretical yield |
An amount that is theoretically produced as calculated using the balanced chemical reaction |
Yields |
theory |
A general statement that explains a large number of observations |
Chemistry as a Science |
thermochemical equation |
A chemical equation that includes an enthalpy change |
Enthalpy and Chemical Reactions |
thiol |
The sulfur analog of an alcohol |
Other Functional Groups |
third law of thermodynamics |
At absolute zero the entropy of a pure, perfect crystal is zero |
Measuring Entropy and Entropy Changes |
titrant |
The reagent of known concentration |
Acid-Base Titrations |
titration |
A chemical reaction performed quantitatively to determine the exact amount of a reagent |
Acid-Base Titrations |
torr |
Another name for a millimeter of mercury |
Pressure |
tracer |
A substance that can be used to follow the pathway of that substance through a structure |
Uses of Radioactive Isotopes |
transition state |
The highest energy transitional point in the elementary step |
Reaction Mechanisms |
triple bond |
A covalent bond composed of three pairs of bonding electrons |
Covalent Bonds |
unsaturated hydrocarbons |
A carbon compound with less than the maximum possible number of H atoms in its formula |
Hydrocarbons |
unsaturated solution |
A solution with less than the maximum amount of solute dissolved in it |
Some Definitions |
valence electrons |
The electrons in the highest-numbered shell, plus any electrons in the last unfilled subshell. The electrons most likely involved in chemical reactions |
Electronic Structure and the Periodic Table |
valence shell |
The highest-numbered shell in an atom that contains electrons |
Electronic Structure and the Periodic Table |
valence shell electron pair repulsion theory (VSEPR) |
The general concept that estimates the shape of a simple molecule: electron pairs repel each other to get as far away from each other as possible |
Molecular Shapes and Polarity |
van der Waal’s equation |
An equation which compensates for deviations from ideal gas behaviour, correcting for intermolecular forces and the volume of gas molecules |
Real Gases |
van’t Hoff factor (i) |
The number of particles each solute formula unit breaks apart into when it dissolves |
Colligative Properties of Ionic Solutes |
vapor |
Material in the gas phase due to evaporation |
Properties of Liquids |
vapor pressure |
The partial pressure exerted by evaporation of a liquid |
Gas Mixtures |
vapor pressure depression |
The decrease of a solution’s vapor pressure because of the presence of a solute |
Colligative Properties of Solutions |
vector quantity |
A quantity which has both a magnitude and direction |
Molecular Shapes and Polarity |
voltaic (galvanic) cell |
An apparatus that allows for useful electrical work to be extracted from a redox reaction. |
Applications of Redox Reactions: Voltaic Cells |
wavelength |
The distance between corresponding points in two adjacent light cycles |
Light |
weak acid |
Any acid that is less than 100% dissociated into ions in aqueous solution |
Strong and Weak Acids and Bases and Their Salts |
weak base |
Any base that is less than 100% dissociated into ions in aqueous solution |
Strong and Weak Acids and Bases and Their Salts |