2. Gases
• In gases, the particles of a substance are far
apart and moving.
3. Gases
• Gas particles expand to fill the container they
are in.
• When the particles hit the sides of the
container they exert a f_____ on the container
• The total f_____ of all these collisions is called
the p_______ of the gas
4. Temperature and pressure
• The pressure of a gas depends on how many
particles there are and how fast they are moving
• If I h____ the particles they move faster, collide
with the walls of the container m______
• If the size of the container can change, the
v_______ will increase and the p_____ will stay
the same
• If the size of the container can’t change, the
v_____ stays the same and the p______
increases
5. Volume of gas
• The volume of a gas is governed by three
things – its pressure, its temperature and the
number of the particles
• If volume, pressure and temperature are all
the same, we have the same number of
particles no matter what the particles are.
• As chemists, we count particles in moles
• One mole of any gas occupies the same
volume at the same temperature and pressure
6. Room Temp and Pressure (RTP)
• Room temperature and pressure (RTP) is
defined as 25°C and 1 atmosphere pressure
• At RTP, I mole of any gas occupies 24dm3
• Moles = vol of any gas at RTP
24