Science - The Atmosphere - The Air Around You

Circle the letter of each sentence that is true about nitrogen.

- A nitrogen molecule has two nitrogen atoms. - Nitrogen is a gas. - Nitrogen makes up more of the air than any other gases.

Circle the letter of each sentence that I true about *carbon dioxide*.

- It is essential to life. - It is given off by plants and animals as a waste product. - It is needed by fuels to burn.

Circle the letter of each sentence that is true about *oxygen*.

- It is needed to release energy from food. - It is released by fuels when they burn. - It may form ozone when it interacts with lightning.

How many times more does nitrogen than oxygen make up air?

57%

What percentage of air is made up of nitrogen and oxygen together?

99%

What role does water vapor play in Earth's weather?

Clouds form when water vapor condenses out of the air to form tiny droplets of liquid water or crystals of ice. If theses droplets or crystals become heavy enough, they can fall as rain or snow.

Is the following sentence true or false? Carbon dioxide alone makes up almost 1 percent of dry air.

False

Is the following sentence true or false? Water vapor is the same as steam.

False

Gases in Dry Air

Nitrogen - 78% Oxygen - 21% All other gases -1%

How does Earth's atmosphere make conditions on Earth more suitable for living things?

The atmosphere contains oxygen and other gases that you and other living things need to survive.

What particles does air contain?

Tiny solid and liquid particles of *dust, smoke, salt, and other chemicals*.