1. Properties of Gases

2. Kinetic Theory and Gases
Simple kinetic molecular theory (KMT) can be used to explain the behavior of gases.

3. COMPRESSIBILITY
Compressibility is a measure of how much the volume of matter can decrease under pressure.

4. Compressibility of Gases
According to the KMT gas particles are so small in relation to the distances between them that their individual volumes are virtually insignificant. This means that there is a lot of empty space between the individual gas particles. This space between the particles explains why gases can be compressed.

5. Freedom of movement…
According to the KMT there are no repulsive or attractive forces between gas particles. As a result gas particles are free to move and expand as far as their container will allow them to.

6. Constant random motion…
The KMT also states that gas particles move in straight paths independently of each other. Only when a particle collides with another particle will their path change.

7. Perfectly elastic collisions
The kinetic molecular theory assumes that the collision of gas particles are perfectly elastic and that the total amount of kinetic energy is conserved within the system.

8. VARIABLES THAT DESCRIBE GASES
Pressure (P)
Temperature (T)
Volume (V)
Number of Moles (n)

9. GAS PRESSURE
Gas pressure is defined as the force exerted by a gas per unit surface area of an object. This force is the result of simultaneous collisions of billions of gas molecules with the surface of the container.
Pressure The symbol for pressure is P and the unit of measurement is Pascal.
1 atm = Pascal = 760 mm Hg

10. TEMPERATURE
According to the KMT the average kinetic energy of a collection of gas is directly proportional to the temperature of the gas when measured in Kelvin units.
0 degrees Celsius = 273 Kelvin

11. VOLUME Volume is the amount of space occupied by a substance.
The symbol for volume is V and it is measured in liters.

12. Number of moles
The number of moles represents the number of particles contained in a system.
6.02X particles = 1 mole

13. How can you increase the pressure of a gas?

14. Ways to Increase the Pressure of a Gas
Increase the number of moles of gas in a container that has a fixed volume.
Increase the temperature of a gas.
Reduce the volume of a container.