the nature of gases section 10.1 after reading section 10.1, you should know: the three assumptions...

THE NATURE OF GASESSECTION 10.1

After reading Section 10.1, you should know:

• the three assumptions of the kinetic theory

• how to convert pressure readings between atm, kPa and mm Hg

• how the kinetic theory affects gas pressure

Kinetic Theory

Atoms are in constant motion

3 Assumptions of the Kinetic Theory for gases: No attractive or repulsive forces exist between

gas particles The particles in a gas are in constant, random

motion All collisions are perfectly elastic

kinetic energy is transferred from one particle to the next without losing any energy

Gas Pressure

The force exerted by a gas per unit of surface area

A vacuum exists if there is no gas particles or pressure

1 atm = 760 mm Hg = 101.3 kPa

Gas Pressure

Atmospheric Pressure – force exerted from collisions of air particles with objects

Measured with a barometer

Kinetic Energy and Kelvin Temperature Particles absorb energy, which causes them

to move faster This increase in kinetic energy causes the

temperature to rise

At absolute zero (0 Kelvin) the molecules have no kinetic energy and are no longer moving

Kinetic energy and Kelvin temperature are directly related

After reading Section 10.1, you should know:

• the three assumptions of the kinetic theory

• how to convert pressure readings between atm, kPa and mm Hg

• how the kinetic theory affects gas pressure