2. Air’s density changes two ways

3. heat

4. What happens to the air pressure on my head as the temperature increases?

6. Air pressure is usually lower when air (1) gets colder (2) gets warmer (3) increases in density (4) weighs more

9. Atomic Mass tells us How dense the atom is.

10. 14 amu + 14 amu = 28 amu 16 amu + 16 amu = 32 amu 1 amu + 1 amu + 16 amu = 18 amu

11. Dry Air (mostly N 2 & O 2 ) Moist Air (more H 2 O less N 2 or O 2 )

13. Air pressure is usually lowest when the air is (1) warm and dry (2) warm and humid (3) cool and dry (4) cool and humid

14. Air pressure is usually highest when the air is (1) cool and humid (2) cool and dry (3) warm and humid (4) warm and dry