Metals and Non-metals | Activities in Text Book with Solution
Activity 3.14Take three test tubes and place clean iron nails in each of them.
Label these test tubes A, B and C. Pour some water in test tube A and cork it.
Pour boiled distilled water in test tube B, add about 1 mL of oil and cork it. The oil will float on
water and prevent the air from dissolving in the water.
water and prevent the air from dissolving in the water.
Put some anhydrous calcium chloride in test tube C and cork it. Anhydrous calcium chloride will absorb the moisture, if any, from the air. Leave these test tubes for a few days and then observe (Fig. 3.13).
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| Fig. 3.13 |
✅ Answer:
After few days, the iron nails rust
in test tube A, but they do not rust in test tubes B and C.
In test tube A, the nails are
exposed to both air and water.
In test tube B, the nails are
exposed to only water.
The nails in test tube C are
exposed to dry air.
This shows that both air and
moisture are needed for rusting of iron.