1. 11-1
What is air?

2. Air is matter…it has mass and volume.
A Mixture of Gases
Air is made mostly of nitrogen (78%) and oxygen (21%) and other trace gases.
Air is matter…it has mass and volume.

3. Nitrogen
Bacteria have to change nitrogen gas into nitrogen compounds that living things can use.
Plants get N compounds from the ground, then animals get N compounds by eating the grass.

4. Oxygen Living things need oxygen to carry on cellular respiration.
Cellular respiration- process by which a cell releases energy from food molecules.
As O is breathed in, this process is completed.

5. Carbon Dioxide
Carbon dioxide is given off by things burning…such as in pollution.
Humans also give off carbon dioxide as a byproduct of breathing.
Plants then take in carbon dioxide to make their food.
(Draw 2 and 3).

6. Components in Air
Gases such as N, O, and CO2.
Water vapor- steam- gases.
Tiny particles of dust, smoke, salt, and other chemicals.