Question

write the letter of the correct answer on the line at the left. 1. the measure of the average energy of motion of the particles in a substance is a. temperature. b. chemical energy. c. pressure. d. viscosity. 2. a liquid has a a. constant temperature. b. definite shape. c. crystal structure. d. definite volume. 3. the change from a gas to a liquid is called a. evaporation. b. condensation. c. melting. d. sublimation. 4. which of the following is not a characteristic of crystalline solids? a. particles arranged in repeating patterns b. becomes softer and softer as temperature rises c. made up of crystals d. has a distinct melting point 5. boyles law states that as the pressure of a gas increases, its a. volume increases. b. temperature increases. c. volume decreases. d. temperature decreases. 6. which of the following is not an example of vaporization? a. dry air gains water as it moves over the ocean b. bubbles form as water boils c. wet pavement dries after a rain shower d. water droplets form on a mirror 7. a substance which takes the shape and volume of its container is a a. solid. b. liquid. c. gas. d. crystal. 8. which of the following is an example of a chemical change? a. twisting a wire b. water freezing c. a pond drying up d. burning gasoline producing carbon dioxide

Explanation:

1. Temperature is the measure of the average kinetic - energy of particles in a substance.
2. Liquids have a definite volume but take the shape of their container.
3. Condensation is the change from a gas to a liquid.
4. Crystalline solids have a regular particle arrangement, are made of crystals, and have a distinct melting point. They don't become softer gradually as temperature rises like amorphous solids.
5. Boyle's Law states that for a given mass of gas at constant temperature, pressure and volume are inversely proportional.
6. Vaporization is the change from liquid to gas. Water droplets forming on a mirror is condensation.
7. Gases take the shape and volume of their container.
8. A chemical change results in the formation of new substances. Burning gasoline to produce carbon dioxide is a chemical change.

Answer:

1. a. temperature
2. d. definite volume
3. b. condensation
4. b. becomes softer and softer as temperature rises
5. c. volume decreases
6. d. water droplets form on a mirror
7. c. gas
8. d. burning gasoline producing carbon dioxide