Chemistry 12 Chapter 7 Exemplar Solutions the P Block Elements Part 8
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VI. Long Answer Type
Question 70:
An amorphous solid βAβ burns in air to form a gas βBβ which turns lime water milky. The gas is also produced as a by-product during roasting of sulphide ore. This gas decolourises acidified aqueous solution and reduces Identify the solid βAβ and the gas βBβ and write the reactions involved.
Answer:
Question 71:
On heating lead (II) nitrate gives a brown gas βAβ. The gas βAβ on cooling changes to colourless solid βBβ. Solid βBβ on heating with changes to a blue solid βCβ. Identify βAβ, βBβ and βCβ and also write reactions involved and draw the structures of βBβ and βCβ.
Answer:

Structure N2O4

Structure N2O3
Question 72:
On heating compound (A) gives a gas (B) which is a constituent of air. This gas when treated with of hydrogen in the presence of a catalyst gives another gas (C) which is basic in nature. Gas C on further oxidation in moist condition gives a compound (D) which is a part of acid rain. Identify compounds (A) to (D) and also give necessary equations of all the steps involved.
Answer:
(i)
(ii)
(iii)