Gas Laws

Flashcards on Gas Laws and States of Matter

Gas

Matter that has indefinite shape and volume, very low density, is highly compressible, has a high rate of diffusion and exerts pressure.

Liquid

Matter that has indefinite shape, definite volume, relatively high density, is relatively incompressible, has the ability to diffuse and has surface tension.

Solid

Matter that has definite shape and volume, very high density, is the least compressible, and has a low rate of diffusion.

Amorphous Solid

Solid with random arrangement of particles; examples are glass and plastic.

Crystalline Solid

Solid that exist as single crystal or group of crystals with definite, organized arrangement and very strong attraction; four types are ionic crystals, covalent network, covalent molecular, metallic crystals.

Ionic Crystals

Crystals with ionic bonds, high melting point, good insulators, hard and brittle, not a good conductor (only good in solution), and strong bonds. (Salt)

Covalent Network Crystals

Crystals with strong covalent bonds, high melting point, semi or non-conductors, hard and brittle; arrangement determines properties. Diamond/quartz are good examples.

Covalent Molecular Crystals

Crystals held together by intermolecular forces NOT sharing electrons, lower melting/boiling point, good insulators, relatively soft. (ice)

Metallic Crystals

Crystals with metal atoms surrounded by delocalized “sea of electrons”/metallic bonding, very high density, excellent conductors, malleable, ductile, luster.

Sublimation

Change of state from solid to gas.

Deposition

Change of state from gas to solid.

Boiling

Change of state from liquid to gas; escape from entire sample, needs to be heated.

Evaporation

Change of state from liquid to gas; escape from surface only, doesn't need to be heated.

Triple Point

Point on a phase diagram where a substance exists in all three states.

Molar heat of fusion

Energy needed to change substance from solid to liquid.

Molar heat of vaporization

Energy to change substance from liquid to gas.

Kinetic Molecular Theory

Attempts to explain behavior of an ideal gas; Gases consist of tiny particles, Volume of individual particles is negligible, Particles are in constant, random motion, Force of attraction between is very weak, Collisions are elastic and exert pressure, Kinetic energy is directly proportional to the temperature (in Kelvin) of the gas.

Pressure

Force/Area

STP

Conditions are 1 atm and 273 K and 1 mole of gas at STP = 22.4 L

Boyle’s Law

Pressure and Volume are inversely proportional at constant temperature and moles of gas

Charles's Law

Volume and Temperature are directly proportional at constant pressure and moles of gas; when something is heated, it expands and when something is cooled, it contracts

Amonton’s Law

Pressure and temperature are directly proportional at constant volume and amount of gas

Avogadro’s Law

Volume and # of moles are directly proportional at constant pressure and temperature.

Ideal Gas Law

This law applies to ideal gases; A real gas deviates from ideal gas behavior at very low temperatures and high pressure.

Dalton’s Law of Partial Pressure

The pressure of a mixture of gases is equal to the sum of pressures of the individual gases; A gas’s individual pressure is proportional to the amount of mixture comprises.

Graham’s Law

The rate at which gases effuse or diffuse is inversely proportional to the square root of their densities.