Why does water expand as it freezes? A. In ice, molecules are less densely packed because they move more slowly.

B. Ice molecules expand so they have more volume than liquid water molecules have.

C. Intermolecular forces increase to balance the loss of heat during freezing.

D. Hydrogen bonding creates an arrangement of molecules in ice that includes more open space.

Match the following vocabulary terms to their definitions. 1. amount of energy required to change 1 gram of material from the solid to the liquid state at its melting point 2. a measure of the kinetic energy of the particles of a substance 3. the amount of heat energy required to raise the temperature of 1 gram of liquid water from 14.5°c to 15.5°c 4. amount of energy required to change 1 gram of material from the liquid to the gaseous state at its boiling point 5. the amount of energy required to change 1 gram of a substance 1°c a. temperature b. latent heat of vaporization c. latent heat of fusion d. calorie e. specific heat

Which sentence about particles in matter is true? a. atoms are present in solids and liquids but not in gases. b. the particles of matter are in constant motion. c. the same kinds of atoms are found in different elements. d. when a solid changes to a liquid, the sizes of the particles change.

Stage in which a star’s outer layers have started to cool and grow outward?