Gases

Gas

A substance that has no well defined boundaries but diffuses rapidly to fill any container in which it is placed

Boyles law

As a constant temperature, the volume of a given mass of any gas is inversely proportional to the pressure of the gas. P~1/V

Charles law

Had a constant pressure the volume of a given mass of any gas is directly proportional to the Kelvin temperature. V~T

Gay Lussacs law

When a gas reacts the volume consumed in the reaction bear a simple whole number ratio to each other and the volumes of any gaseous product of the reaction if all volumes are measured under the same conditions of temperature and pressure

Avogadros law

Equal volumes of gases contain equal numbers of molecules under the same conditions of temperature and pressure

Ideal gas

A gas that obeys all the assumptions of the kinetic theory of gases under all conditions of temperature and pressure

Why do real gases differ

. Intermolecular forces are present

Molecules have volume

Collisions are not perfectly elastic

Assumptions of the kinetic theory

1. Particles are constantly moving and colliding with themselves and container walls

2. No attractive/repulsive forces

3. gases are made of a particles whose diameters are negligible compared to the distance between them

4. Average kinetic energy is proportional to temp of gas in kelvin

5. All collisions are perfectly elastic.

When do gases behave like ideal gases

Real gases become more like ideal gases at low pressure and high temperature

What is stp

Standard temperature and pressure

Scientist realise that the pressure and temperature controlled the volume observed for gas sample therefore to compare different gas samples they defined a set of reference conditions

Ideal gas law

PV=nRT

Combined gas law