Oxidation of Metals by Nitric Acid

How does nitric acid react with silver and gold?

What happens when silver is exposed to nitric acid?

Why is gold resistant to oxidation by nitric acid?

Answer:

Silver is oxidized by nitric acid to form silver nitrate, while gold is resistant and doesn't undergo oxidation.

Explanation: In nitric acid, silver undergoes oxidation while gold is resistant to oxidation. This is due to the difference in reactivity of the metals.

Concentrated nitric acid reacts with silver to form silver nitrate. The reaction can be represented by the equation:

2Ag(s) + 4HNO3(aq) → 2AgNO3(aq) + 2H2O(l) + NO2(g)

On the other hand, gold is resistant to oxidation by nitric acid, even concentrated ones. This is because gold is less reactive compared to silver, and its protective oxide layer prevents further reaction with the acid. Therefore, gold remains unchanged in the presence of nitric acid.