1. What kind of energy is stored in bonds of molecules?

1. 1. What kind of energy is stored in bonds of molecules? SKIP A PAGE IN YOUR NOTEBOOK! THURSDAY, OCTOBER 27 • Thermal energy • Chemical energy • Nuclear energy • Mechanical energy

2. 2. The flow of thermal energy is called • Temperature • Heat • Kinetic energy • A circuit

3. 3. In a hydroelectric power plant, moving water turns a turbine, which generates electricity. What energy conversion takes place in the turbine? • Thermal to electrical • Electrical to mechanical • Thermal to mechanical • Mechanical to electrical

4. 4. Which of these statements about mixtures is false? • A mixture is made up of two or more pure substances. • A mixture can be separated by physical means. • One of the substances in a mixture must be a liquid. • A mixture does not have a definite makeup.

5. 5. To activate a “light stick,” you bend the stick until the vial inside breaks. Then you shake the stick to mix the contents. The stick will glow for several hours. What energy transformation takes place in a light stick? • Mechanical energy to radiant energy • Chemical energy to mechanical energy • Chemical energy to radiant energy • Radiant energy to thermal energy

6. 6. A rock falls from the edge of a cliff. Which sentence describes the rock’s energy when it is exactly halfway between the cliff edge and the ground? • Its kinetic energy equals its potential energy. • Its kinetic energy is twice its potential energy. • Its kinetic energy is less than its potential energy. • Its kinetic energy is greater than its potential energy.

7. Halloween Activities • The change in phase from a solid directly to a gas is called ______________. An example is _________________________. • A _____________ is a substance that gets dissolved in something else. An example is _________________________. • A ______________ is what a substance gets dissolved in. _____________ is called the universal _________ because almost everything will dissolve in it. • In class, Tang was an example of a ___________. sublimation dry ice solute Powdered Tang solvent Water solvent solution

8. pH scale: a scale from 1 to 14. • Anything with a pH of <7 is an acid. Ex: vinegar • Anything with a pH of >7 is a base. Ex: baking soda • Anything with a pH of 7 is neutral. Ex: water • “Bloody handprints” are a chemical reaction between special paper and a base. Reaction is reversed in vinegar.

9. Standard S8P1 D. Distinguish between physical and chemical properties of matter as physical (i.e. density, melting point, boiling point) or chemical (i.e. reactivity, combustibility). E. Distinguish between changes in matter as physical (i.e. physical change) or chemical (i.e. development of a gas, formation of precipitate, and change in color).

10. “Bloody” handprints Students in Mrs. Youmans’ science classes dipped their hands in a basic solution of baking soda and water, which reacted with specially treated goldenrod paper to create the illusion of “bloody” handprints. They could then dip their hands in a mildly acidic solution of vinegar and water to reverse the chemical reaction and turn the paper back to its original color. Happy Halloween!

11. 7. What happens to most materials when they become warmer? • They contract. • They float. • They vaporize. • They expand.

12. 8. Which of the following is true? • Warm air is less dense than cool air. • Warm air is as dense as cool air. • Warm air has no density. • Warm air is denser than cool air.

13. 8. Convection currents do not take place in • Liquids • Gases. • Solids. • The ocean.

14. 9. The transfer of heat by collision of atoms is • conduction. • Convection. • Radiation. • Thermal energy.