Sc 7: pp 160-163

Front

What are the percentages of nitrogen, oxygen, and other gases in the atmosphere?

Back

Nitrogen: 78%, Oxygen: 21%, Other gases: 1%.

Front

Are the layers of the atmosphere divided by temperature changes?

Back

True.

Front

Do gas molecules become increasingly closer together as the distance from Earth's surface increases?

Back

False.

Front

Where are most clouds found in the atmosphere?

Back

Most clouds are found in the troposphere, not the stratosphere.

Front

What layer of the atmosphere provides the oxygen that most organisms need?

Back

Troposphere.

Front

What is the primary gas in the Earth's atmosphere?

Back

Nitrogen.

Front

What is the second most abundant gas in the atmosphere?

Back

Oxygen.

Front

What is the role of the stratosphere?

Back

The stratosphere contains the ozone layer, which protects Earth from harmful UV radiation.

Front

What happens to temperature as you move higher in the troposphere?

Back

Temperature decreases as altitude increases in the troposphere.

Front

What is the boundary between the troposphere and the stratosphere called?

Back

Tropopause.