1. Does air have mass?

2. Because air has mass it also has other properties including:
Density
Pressure

3. Density
Amount of mass in a given volume
D=M/V

4. Pressure The force pushing on an area or surface
Air pressure is a result of the weight of a column of air pushing down on an area
Why doesn’t air pressure crush us?
1000ml = 1.2g

5. Tool used to measure air pressure
Barometer
2 types
Mercury barometer-

6. Aneroid barometer (without liquid)-

7. Air pressure measured in:
millibars
inches of mercury
1 inch of mercury = mb

8. Altitude and the properties of air
Altitude – distance above sea level
As altitude increases air pressure decreases
When air pressure decrease density decreases