U5L3 Classifying Reactions Portfolio Wo

Classifying Reactions

Safety Reminder: Wear safety glasses and conduct experiment in a well-ventilated area.

Day 1

Materials:

Part I: steel wool (HEB, Target, Lowe’s, Home Depot) You can also try SOS pads. tweezers vinegar test tube (in your kit) water petri dish (in your kit)

Part II: hydrogen peroxide small pieces of raw potato (yeast or beef liver may be substituted for the potato) small bowl

Procedures:

Part I: Reaction between iron and oxygen

1. Break off a small piece of steel wool and soak it in vinegar for at least one minute. Use tweezers to push the steel wool around to remove all bubbles.
2. Using the tweezers, lift the steel wool out of the vinegar and shake if gently over a paper towel.
3. Stretch the steel wool out (don’t wad it up) and gently push it into the bottom of a test tube.
4. Add water to the petri dish until the water is approximately three-quarters of an inch deep.
5. Invert the test tube and place it in the petri dish of water.
6. At this point no water should be in the test tube. You have essentially trapped a test tube full of air in the water-filled dish.
7. Allow to stand for 20 minutes and then record your observations.
8. While the mixture is standing, complete Part II of the lab. Be sure to record your observations for Part I after 20 minutes.

Part II: Decomposition of hydrogen peroxide

1. Pour one third of a cup of hydrogen peroxide into a small bowl.
2. Cut up several small pieces of raw potato and place them in the hydrogen peroxide.
3. Record your observations.

Observations:

Part I: Reaction between iron and oxygen

Appearance of steel wool after 20 minutes __________________it still looked the same___________________

Part II: Decomposition of hydrogen peroxide

Appearance of potato and hydrogen peroxide combination ___________alot of foam came out of the potato because of the Hydrogen peroxide_____________

Day 2

Materials:

Part III: a penny dated after 1983 metal file or coarse sandpaper (if