The Gas Laws and Chemical Reactions

A comprehensive set of practice flashcards covering atmospheric gas laws, the ideal gas equation, Dalton's law of partial pressures, and the classification and balancing of chemical reactions.

Boyle’s Law

A gas law stating that when the temperature is held constant, the volume of a given mass of gas varies inversely with the pressure ($P_1V_1 = P_2V_2$).

Charles’s Law

A gas law stating that the volume of a given mass of gas varies directly with the absolute temperature of the gas when pressure is kept constant ($V_1 / T_1 = V_2 / T_2$).

Absolute Temperature

Temperature measured with the Kelvin scale, where zero corresponds to a complete stop of molecular motion.

Avogadro's Law

Provides the relationship between volume and amount (moles) of a gas when pressure and temperature are held constant ($V_1 / n_1 = V_2 / n_2$).

Gay-Lussac’s Law

Describes the relationship between pressure and temperature of a gas at constant volume, where pressure increases proportionally as temperature increases ($P_1 / T_1 = P_2 / T_2$).

Combined Gas Law

Describes the relationship between pressure, volume, and temperature of a gas when the amount of gas is constant ($P_1V_1 / T_1 = P_2V_2 / T_2$).

Ideal Gas

A theoretical gas composed of randomly-moving point particles that interact only through elastic collisions and move freely in all directions.

Ideal Gas Equation

Written as $PV = nRT$, where $P$ is pressure, $V$ is volume, $n$ is the amount in moles, $R$ is the gas constant, and $T$ is temperature in Kelvin.

Universal Gas Constant ($R$)

A proportionality constant in the ideal gas equation with a numerical value such as $0.08206\,L \cdot atm/mol \cdot K$ or $8.314\,J/mol \cdot K$.

STP (Standard Temperature and Pressure)

Reference conditions defined by scientists as $0^\circ C$ ($273.15\,K$) and $1\,bar$ ($10^5\,Pa$) pressure.

Dalton’s Law of Partial Pressures

A gas law stating that the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures exerted by each individual gas ($P_{total} = P_1 + P_2 + P_3 + \dots$).

Mole Fraction ($X$)

The ratio of the moles of one substance in a mixture to the total number of moles of all substances present ($X_A = n_A / n_{total}$).

Chemical Reaction

A process associated with chemical change where old chemical bonds are broken and new chemical bonds are formed to create new products.

Word Equation

A description of a chemical change using the names of the reactants and products rather than chemical symbols.

Law of Conservation of Mass

A principle stating that total mass must be equal on both sides of a chemical equation, requiring the number of each type of atom to be equal.

Combination Reaction

A type of reaction in which two reactants combine to form a single product ($A + B \rightarrow AB$).

Decomposition Reaction

A type of reaction in which a single reactant breaks down into two or more simpler products ($AB \rightarrow A + B$).

Single-displacement Reaction

A reaction in which one element replaces or displaces another element in a compound ($A + BC \rightarrow AC + B$).

Double-displacement Reaction

A reaction where the positive ions of two compounds exchange places to form two new compounds ($AB + CD \rightarrow AD + CB$).

Stoichiometry

The calculation of the quantities of reactants and products in chemical reactions based on a balanced chemical equation.