Unit 1: Gas Laws and States of Matter

Comprehensive vocabulary flashcards covering the kinetic theory of matter, temperature and pressure scales, specific gas laws (Boyle's, Charles's, Gay-Lussac's, Avogadro's), and the properties of real versus ideal gases.

Temperature

A measure of the average Kinetic Energy (energy of motion) of the particles in a substance.

Absolute Zero

The temperature at which particle movement (KE), pressure, and volume are zero, equivalent to $0\,K$ or $$-273.15^\circ C$.

Pressure

The force exerted per unit area by collisions of particles with each other and the surfaces of their container ($P = \text{Force/Area}$).

Atmosphere (atm)

A unit of pressure equivalent to the amount of atmospheric air pressure at sea level and normal temperatures; $1\,atm = 101.3\,kPa = 760\,mm Hg = 14.7\,psi$.

Kilopascal (kPa)

The most commonly used metric unit of pressure, where $101.3\,kPa$ is equivalent to $1\,atm$.

Solid

A state of matter with a definite shape and volume where particles vibrate in fixed positions.

Liquid

A state of matter with a definite volume that takes the shape of its container; particles remain tightly packed but can move around one another.

Gas

A state of matter with no definite volume or shape that spreads out to fill the available space; particles move independently.

Plasma

A state of matter with no definite shape or volume containing ionized (charged) particles that usually emit light.

Sublimation

The phase change where a substance transitions directly from a solid to a gas.

Deposition

The phase change where a substance transitions directly from a gas to a solid.

Equilibrium

A balance between two opposite processes, such as when water vaporizes at the same rate that it condenses.

Evaporative Cooling

The cooling of a surface caused by the loss of high kinetic energy particles during evaporation, leaving lower KE particles behind.

Vapor Pressure

The pressure exerted by a vapor above a liquid in a closed container; it increases as temperature increases.

Boiling

The transition from liquid to gas occurring when vapor pressure equals atmospheric pressure, characterized by bubbles forming inside the liquid.

Evaporation

The transition from liquid to gas occurring at the surface of the liquid when vapor pressure is below atmospheric pressure.

Normal Boiling Point

The specific temperature at which a substance boils when the atmospheric pressure is exactly $1\,atm$.

Triple Point

The specific temperature and pressure combination at which a substance exists as a solid, liquid, and gas simultaneously.

Kinetic Molecular Theory (KMT)

A set of five assumptions describing ideal gas behavior, including constant random motion, negligible particle volume, and elastic collisions.

Boyle’s Law

The gas law stating that pressure and volume are inversely proportional ($P_1V_1 = P_2V_2$) when temperature and amount are constant.

Charles’s Law

The gas law stating that volume and Kelvin temperature are directly proportional ($\frac{V_1}{T_1} = \frac{V_2}{T_2}$) when pressure and amount are constant.

Gay-Lussac’s Law

The gas law stating that pressure and Kelvin temperature are directly proportional ($\frac{P_1}{T_1} = \frac{P_2}{T_2}$) when volume and amount are constant.

Avogadro’s Law

The gas law stating that volume and the amount of gas (moles) are directly proportional ($\frac{V_1}{n_1} = \frac{V_2}{n_2}$) when pressure and temperature are constant.

Combined Gas Law

An equation relating pressure, volume, and temperature for a constant amount of gas: $\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}$.

Ideal Gas Law

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

Real Gas

A gas that deviates from ideal behavior because particles have volume and experience attractive/repulsive forces, typically at low temperatures and high pressures.

Ideal Gas Constant (R)

A constant value in the ideal gas law, either $0.0821\,L\cdot atm / mol\cdot K$ or $8.31\,L\cdot kPa / mol\cdot K$ depending on pressure units.