Physical and Chemical Changes Review

What must occur before clouds can form?

• Water vapor must get warmer.
• Water vapor must lose heat energy.
  
• Precipitation must begin to fall and run off.
• Transpiration must add water vapor to the atmosphere.

In which way are evaporation and condensation similar?

• Both cause decreases in air temperature.
• Both cause increases in air temperature.
• Both are caused by the warming of the atmosphere.
• Both are caused by changes in heat energy.

Which process allows green plants to control the amount of water stored in their leaves?

• photosynthesis
• evaporation
• transpiration
• condensation

If 10 grams of water are added to 5 grams of salt, how much salt water will be made?

• 2 grams
• 5 grams
• 10 grams
• 15 grams

Which is an example of a different substance being formed?

• glass breaking
• metal melting
• water freezing
• wood burning

A student makes a model of the water cycle by putting water in a cup, and placing plastic wrap on the top of the cup.  The student then places the cup by a sunny window.  Which best explains why the student placed the model near a sunny window?

• The thermal energy from the sun will start the process of evaporation in the model.
• The light energy from the sun will start the process of evaporation in the model.
• The mechanical energy from the sun will start the process of evaporation in the model
• The electrical energy from the sun will start the process of evaporation in the model.

Which of the following best explains how condensation occurs?

• Heat energy from the sun is increased, causing water vapor to condense
• Water travels to the sun, and then condenses into clouds
• Water in the air always turns to liquid when it comes in contact with a surface
• Heat energy from the sun is decreased, causing the water vapor to cool and condense

Which of the following changes to matter will result in a new substance with new properties?

• Breaking glass
• baking a cake
• boiling water
• chopping wood

Which fact best explains why most evaporation happens in the oceans?

• Ocean water is salty.
• There are mountain ranges on the ocean floor.
• About 97 percent of Earth’s water is ocean water.
• Fewer clouds block sunlight over the ocean.

Ricco is making paper air planes. He uses 5 grams of paper to make 10 paper airplanes. If he weighs the paper airplanes, which is their total mass?

• 5 grams
• 10 grams
• 15 grams
• 20 grams