The Nature and Structure of Matter
Objective 3: Physical and Chemical Changes:
Part A: Put a P in the blank for PHYSICAL change, C for CHEMICAL change or B if it describes BOTH types of change.
- An ice cube is placed in the sun. Later there is a puddle of water and later still the water is gone. _____
- Two chemicals are mixed and a gas is produced. _____
- A bicycle changes color as it rusts. _____
- A solid is crushed to a powder. _____
- Two substances are mixed and light is produced. ____
- A piece of ice melts and reacts with sodium. _____
Part B: Read each paragraph below and decide whether a PHYSICAL or a CHEMICAL change as occurred.
- Ummm! A loaf of bread hot from the oven. You cut yourself a slice and spread it with butter. What kind of change occurred when you cut the loaf of bread?______
- Your friend decides to toast a piece of the bread, but leaves it in the toaster too long. The bread is black and the kitchen is full of smoke. What kind of change has the bread undergone? ______
- You forgot to dry the bread knife when you washed it and reddish-brown spots appeared on it. What kind of change occurred in the metal? ______
- If you blow-dry your hair, what kind of change occurred in the water that was on your hair? ______
- In baking biscuits and other quick breads, the baking powder reacts to release carbon dioxide bubbles, which make the dough rise. What kind of change is this? ______
- It’s time to polish the silverware. The once shiny metal is now dull and, in some places, black. What kind of change has occurred? ______
- A straight piece of wire is coiled to form a spring. What kind of change is this? ______
- Food color is dropped into a clear punch to give it a nice, green tint. What kind of change is this? ______
- Chewing food to break it down into smaller particles represents a ______change, but the changing of starch into sugar by enzymes in the digestive system represents a ______change.
- In a firework show, what change occurs as the fireworks explode, giving off heat/light? ______
Objective 3: Change of State: Match the terms to the descriptions. Some words WILL be used more than once!
Calculating Density, Volume, and Mass:
Use the formula D = M / V for the following problems: SHOW all THREE STEPS for your WORK!
1. 2.5 g and 5 mL
2. 100 g and 2 cm3
3. 675 kg and 25 L
4. 220 cg and 0.5 mL
5. 0.45 g and 3.0 L
6. 0.5 mg and 0.5 mL
Use the formula V = M / D for the following problems: SHOW all THREE STEPS for your WORK!
7. 2.0 g/mL and 222 g
8. 3 g/ cm3 and 88.5 g
9. 10 kg/L and 160 kg
10. 0.5 cg/mL and 25 cg
11. 4.0 g/L and 16 g
12. 12 mg/mL and 936 mg
Use the formula m = D x V for the following problem: SHOW all THREE STEPS for your WORK!
13. 18 g/mL and 100 mL
14. 1.5 g/cm3and 1.5 cm3
15. 145 kg/L and 25 L
16. 10.5 g/mL and 3.5 mL
17. 2 g/mL and 5.1 mL
18. 29 mg/mL and 10 mL