1. SLG

2. Adding thermal energy to a solid normally causes a temperature change in the solid. What happens to the thermal energy and the temperature as the solid melts?
Temperature remains the same; thermal energy goes to breaking solid particles apart.

3. Thermal energy is added to water to turn it into steam
Thermal energy is added to water to turn it into steam. Explain this event according to the kinetic theory of matter.
Water molecules are moving but are held together; as thermal energy is added, molecules move more quickly and are not held as tightly, and some escape as steam.

4. A cold glass will collect moisture on a hot, humid day
A cold glass will collect moisture on a hot, humid day. Explain this event according to the kinetic theory of matter.
Water vapor in air transfers thermal energy to the cooler glass. This slows the molecules, and condensation occurs.

5. Which of the states of matter can you force into a smaller volume
Which of the states of matter can you force into a smaller volume? Explain.
Gas; there is still room between the particles.

6. Explain the thermal expansion of a solid using the kinetic theory of matter.
As thermal energy is added to the solid, the particles gain kinetic energy and move faster. The particles take up a little more room, but they are still held tightly.

7. Explain what happens at the surface of a liquid according to the kinetic theory as thermal energy is added to the liquid.    
Liquid molecules are free to move and have a range of kinetic energies. They will gain kinetic energy from thermal energy, and some particles can fly off the surface if they have enough energy.

8. Explain the purpose of an expansion joint on a bridge.
As the bridge heats in the summer, it becomes longer; in the winter, it becomes shorter.

9. What will happen to the size of a balloon when it is placed in a freezer? Explain.
It shrinks; as the temperature of air decreases, the volume of the air decreases.

10. List the states of matter and explain their differences using the kinetic theory of matter.
solid—particles held tightly, not free to move around; liquid—particles very close together but free to move; gas—particles are free to move in any direction, not held together

11. What strange property of water does a glass of ice water illustrate?
This illustrates the expansion of water as it goes from a liquid to a solid. Because solid water (ice) is less dense than liquid water, it floats.

12. In terms of thermal expansion, why is water unusual?
Water expands when it goes from the liquid to the solid state.

13. Why does water behave in this unusual fashion?
Some parts of the water molecule are negatively charged, and other parts are positively charged. These charged areas align, and the result is space in the solid structure.

14. Why does water’s boiling point decrease with increases in elevation?
Higher elevation results in lower atmospheric pressure. This means the temperature at which the vapor pressure of water equals the atmospheric pressure is also lower.

15. Use the terms definite, not definite, close together, and spread apart to complete the table below.
State
Shape
Volume
Particles
a. Gas
not definite
spread apart
b. Liquid
definite
close together
c. Solid

16. Use the labels heat of vaporization, heat of fusion, stronger, and broken to complete the concept map about energy and changes of state.
Heat of fusion
Heat of vaporization
stronger
broken

17. Complete each of the following diagrams by showing how the positions of the particles will change under the conditions described.

18. Where might you find plasma?
Sun, stars, nuclear reactors, and lightning.