Unit 7: States and Properties of Matter

Vocabulary flashcards from Unit 7, covering states of matter, phase changes, and gas laws.

Thermal energy

The sum of the kinetic and potential energy of particles in an object.

Kinetic energy

Energy in motion.

Potential energy

Stored energy.

Elastic collision

When no kinetic energy is lost overall in the collision of particles.

Temperature

Measure of the average kinetic energy of particles in an object.

Diffusion

Spontaneous mixing of particles caused by random motion.

Effusion

Process where gas particles pass through tiny openings.

Surface tension

Force that pulls adjacent parts of a liquid’s surface together, minimizing the surface area.

Kinetic-molecular theory

Theory stating that all matter is made of small particles that are in constant random motion.

Solid

State of matter with a definite volume, definite shape, and particles that vibrate in place.

Liquid

State of matter with a definite volume, indefinite shape, and particles that slide past each other.

Gas

State of matter with an indefinite volume, indefinite shape, and particles that move freely and collide.

Intermolecular forces

Attractions between different molecules that make up a substance.

Ideal gas

A hypothetical gas that perfectly follows the kinetic-molecular theory with no attractive forces between particles.

Real gas

A gas that doesn’t behave entirely according to the kinetic-molecular theory due to exhibiting attractive forces.

Heat of fusion

The amount of energy needed to turn 1 mole of solid into a liquid at its melting point.

Heat of vaporization

The amount of energy needed to turn 1 mole of liquid into a gas at its boiling point.

Vapor pressure

The temperature at which the vapor pressure of the liquid is equal to atmospheric pressure.

Boiling point

The temperature at which a liquid turns into a gas.

Triple point

Indicates the temperature and pressure conditions necessary for a solid, liquid, and gas of a substance to coexist at equilibrium.

Phase change

A physical change where the identity of the substance doesn’t change, just the energy of the particles.

Sublimation

The process in which a solid changes directly into a gas.

Deposition

The process in which a gas changes directly into a solid.

Pressure

Force per unit area on a surface.

Atmospheric pressure

Pressure exerted by the atmosphere surrounding Earth.

STP

Standard temperature and pressure, which is 1 atm and 273 K.

Partial pressure

The pressure of each gas in a mixture.

Molar volume

The volume that 1 mole of a gas occupies at STP.

Boyle’s Law

The volume of a gas is inversely proportional to its pressure.

Charles’s Law

The volume of a gas is directly proportional to its temperature.

Gay-Lussac’s Law

The pressure of a gas is directly proportional to its temperature.

Combined Gas Law

Relates pressure, volume, and temperature of a gas when the amount of gas is constant.

Ideal Gas Law

The equation PV = nRT, relating pressure, volume, temperature, and the amount of gas.