General Chemistry Flashcards
Acid Dissociation Constant
An equilibrium expression used to measure acid strength, given by the ratio of the product of the products’ molar concentrations to the product of the reactants’ molar concentrations, with each term raised to the power of the its stoichiometric coefficient. Denoted Ka.
Activation Energy
The energy barrier that must be overcome for a reaction to proceed; often denoted by Ea. Activation energy is measured in joules (J).
Adiabatic Process
A process in which no heat is transferred to or from the system by its surroundings.
ex. the vertical flow of air in the atmosphere; air expands and cools as it rises, and contracts and grows warmer as it descends.
Alkali Metals
The highly reactive elements found in Group 1 of the periodic table, except H.
Alkaline Earth Metals
Elements found in Group 2 of the periodic table.
Amphoteric
A species capable of reacting as either an acid or a base. In the Brønsted-Lowry sense, a species that can pick up or give off a proton. In the Lewis sense, a species that can donate or accept a lone pair of electrons.
Anode
The electrode where oxidation occurs during a cell’s oxidation-reduction reaction. Electrons always flow from the anode in an electrochemical cell.
Aqueous Solution
A solution containing water as its solvent.
Arrhenius Definitions
A definition of acids as producers of excess H+ and bases as producers of excess OH- in aqueous solutions
Atomic radius
The distance measured either between the nucleus and outermost electron of an atom or by the separation of the 2 nuclei in a diatomic element. Decreases from L->R and from bottom^top on periodic table
Avogadro’s Principle
States that the number of moles of a gas present is proportional to its volume, assuming constant pressure and temperature
Boyle’s Law
States that at a constant temperature, the volume of an ideal gas is inversely proportional to its pressure
Brønsted-Lowry Definitions
Common definition of acids as proton (H+) donors and bases as proton acceptors
Buffer
A solution containing a weak acid or base coupled with its conjugate salt, acting to prevent changes to the solution’s pH upon the addition of acidic or basic substances.
Cathode
The electrode at which reduction occurs during a cell’s oxidation-reduction reaction. Electrons always flow toward the cathode in an electrochemical.
Charles’s Law
States that at a constant pressure, the volume of an ideal gas is directly proportional to its temperature.
Chemical Kinetics
The study of reaction rates and the factors that affect them.
Closed System
A system that allows for the exchange of energy, but not matter, across its boundaries.
Colligative Properties
The properties of solutions - such as vapor pressure lowering, freezing point depression, boiling point elevation, and osmotic pressure - that are affected only by the number of solute particles dissolved and not by their chemical identities.
Collision Theory of Chemical Kinetics
Theory stating that the rate of a reaction is directly proportional to the number of collisions that take place between reactants per second.
Combination Reaction
A reaction in which 2 or more reactants form a product
ex. 2H2 + O2 -> 2H2O
Common Ion Effect
States that the molar solubility of one salt is reduced when another salt, having a common ion, is brought into the same solution.
Concentration
The ratio of the amount of solute to the amount of solution; quantified by mole fraction, molarity, molality, or normality, among other measures.
Conjugate Acids and Bases
A systematic pairing of a protonated species (acid) with its deprotonated form (conjugate base) or a deprotonated species (base) with its protonated form (conjugated acid). Conjugated appear on opposite sides of a chemical equation.
Constant-Volume Calorimeter
An apparatus commonly referred to as a bomb calorimeter; used to measure the amount of heat absorbed or released during a reaction.
Decomposition Reaction
A chemical reaction in which one substance breaks down into 2 substances
ex. A –> B + C
