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 β€œA” burns in air to form a gas β€œB” 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 β€œA” and the gas β€œB” and write the reactions involved.

Answer:

Question 71:

On heating lead (II) nitrate gives a brown gas β€œA”. The gas β€œA” on cooling changes to colourless solid β€œB”. Solid β€œB” on heating with changes to a blue solid β€˜C’. Identify β€˜A’, β€˜B’ and β€˜C’ and also write reactions involved and draw the structures of β€˜B’ and β€˜C’.

Answer:

Structure N2O4

Structure N2O4

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Structure N2O3

Structure N2O3

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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)