IV. Choose the letter of the BEST correct answer.
16. What causes the rusting of iron nails or
A. Presence of heat B. presence
17. When the candle is lighted, it melted in
minute
What causes these changes?
I. Presence of heat II. Prese
oxygen
A. I, II, and III
B. I and IV
18. What changes will happen to the slices
A. Color will change from brown to v
B. Color will change from white to bi
19. The eggplant/apple in the experiment
NOT TRUE?
A. The presence of the oxygen cause
B. The absence of oxygen caused ch:
C. The color of an apple/ eggplant cl
D. There is oxidation that happened
20. Water is the primary cause of rust be
B. chloride
A. Oxygen​