Unit 2

If a warm wind passes over snow, the snow can be heated rapidly. When this happens, the snow can change directly into water vapor without first becoming liquid water. What is the correct term for this process?

• evaporation

• deposition

• sublimation

• melting

On an island near the equator, the sun's energy causes ocean water to evaporate during the day. In the afternoon, heavy rains fall. This process is repeated during the summer months. What does this example best show?

• How most water on Earth is in the form of water vapor

• How the sun is the main source of energy for the water cycle

• How land is the main source of water during the water cycle

• how the ocean is large enough that it never runs out

A deep ocean current forms when ocean water becomes denser and sinks. The figure shows a deep ocean current.

Based on the illustration, which of the following statements describes the relationship between density and temperature?

• Cold water is denser than warm water

• Warm water is denser than cold water

• Warm and cold water have equal densities

• The density of water is not affected by temperature

What role does heat play in the formation of convection currents?

• When water gains heat, it dissolves more solids and gasses, becomes denser, and sinks

• When water loses heat to cooler water, the cooler water becomes denser and sinks

• When water gains heat, it becomes denser and sinks.

• When water loses heat, it becomes denser and sinks.

Which property of water allows it to form droplets when in liquid form?

• adhesion

• cohesion

• nature as a solvent

• specific heat

Why is Earth's water vapor not found in low places only, as Earth's liquid water is?

• Unlike liquid water, only water vapor can exist in the atmosphere.

• Unlike liquid water, water vapor takes the shape of its container.

• Unlike liquid water, water vapor expands to fill available space.

• Unlike liquid water, water vapor cannot flow downhill.

Which of the following is a measure of the amount of open spaces between the particles of rock and soil?

• porosity

• saturation

• permeability

• precipitation

The table shows the amounts of different types of surface water on Earth.

Based on the table, about how much water is available to provide habitat for wildlife?

• just over 3,000 cubic miles

• nearly 43,000 cubic miles

• about 46,000 cubic miles

• close to 6,000,000 cubic miles

Which of these statements is true of acid rain?

• Acid rain is used for irrigation

• Acid rain has a pH greater than 5.7

• Acid rain is precipitation that causes erosion.

• Acid rain is precipitation that is more acidic than normal.

Humans can cause different types of pollution. When fertilizer and pesticides make their way into water systems, which type of pollution has taken place?

• air

• biological

• chemical

• thermal