51.

State what is observed when:

Nitric acid is kept in a reagent bottle for a long time.

State what is observed when:

Excess of ammonia a passed through an aqueous solution of lead nitrate

Explain why only all-glass apparatus should be used for the preparation of nitric acid by heating concentrated sulphuric acid and potassium nitrate.

Write a chemical equation to illustrate the acidic nature of nitric acid.

Which property of sulphuric acid accounts for its use as a dehydrating agent?

Concentrated sulphuric acid si both an oxidising agent and a non-volatile acid.

Write one equation each to illustrate the above-mentioned properties of a sulphuric acid.

Give reason for the following:

Sulphuric dioxide is used as an antichlor.

Write balanced chemical equations for the following reactions:

Ethane and oxygen in the presence of molybdenum oxide

preparation of methane from anhydrous sodium ethanoate (sodium acetate).

Heating ethanol at 443K (170⁰C) in the presence of concentrated sulphuric acid.