2. Mar 4 / Act D 65
Chemical Batteries
LEARNING TARGET: I can select the best metal combination for a battery and justify with evidence.
CH Q
What combinations of metals makes the best battery to power a small motor?
VOCAB:
Battery; electrolyte; electrochemical cell

3. Battery electrolyte electrochemical cell
chemical reaction device to make electricity
liquid solution that helps conduct electricity
two different metals and salt solution "battery"

4. Both are Potential Chemical Energy sources
DISCUSSION
What do a battery and a peanut have in common when we consider them as sources of energy?
Both are Potential Chemical Energy sources
(battery makes electricity – peanut grows new plant)
2. What goes on inside a battery?
chemical reactions that produce electricity
(moving electrons – small parts of atoms)

5. PROCEDURE AND DATA
MATERIALS:
PROCEDURE: Read on pg. D and summarize
DATA: WS Chemical Batteries

6. EXPECTED RESULTS Metal Combinations Observations Motor Speed Voltage
copper
magnesium
Mg bubbles
Very Fast
1.53
zinc
Cu discolors
Medium
0.84
iron
no change
none
0.38
slow
0.68
(maybe w/ a push)
0.46
Fast
1.20

7. POST DISCUSISON
1. Why did some of the combinations work better than other combinations in providing energy for the motor?
some metals give up electrons more easily (re-active) than others
show TED video

8. 2,000 year old “Baghdad Battery”? (Mythbusters says “possible”
Rank best combo (1) to worst (6)
1. copper + magnesium
2. iron + magnesium
3. copper + zinc
4. zinc + magnesium
5. zinc + iron
6. copper + iron
2,000 year old “Baghdad Battery”?
(Mythbusters says “possible”

9. ANALYSIS
- Discuss and answer Q 2-4 on pg. D 69-70
ANS CH Q
What combinations of metals makes the best battery to power a small motor? A:
copper + magnesium and iron + magnesium
(magnesium gives up electrons very easily)
HOMEWORK
Catch up on Journals – Complete Analysis Q’s