Question

3. State reason for the following:
(i) Small amount of acid is added to water during electrolysis of water.
(ii) When ammonium chloride is dissolved in water in a test tube, the
test tube becomes cold.​

Answer 1

1. Assuming thatdistilled water is being in the experiment, which is a non conductor of electricity we need to make the water conduct electricity for electrolysis to occur. Hence the acid is added. Acids are poured in water to prevent excess of heat.
2. dissolving ammonium chloride in water is endothermic reaction it absorbs heat from the water making the walls of test tube cool

Answer 2

Answer:

I) becoz it contains hydrogen atoms

ii) becoz endothermic reaction occur

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