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The p-Block Elements — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistryThe p-Block Elements5 Marks
Question
An element ‘A’ exists as a yellow solid in standard state. It forms a volatile hydride ‘B’ which is a foul smelling gas and is extensively used in qualitative analysis of salts. When treated with oxygen, ‘B’ forms an oxide ‘C’ which is a colourless, pungent smelling gas. This gas when passed through acidified $KMnO_4$ solution, decolourises it. ‘C’ gets oxidised to another oxide ‘D’ in the presence of a heterogeneous catalyst. Identify ‘A’, ‘B’, ‘C’, ‘D’ and also give the chemical equation of reaction of ‘C’ with acidified $KMnO_4​​​​​​​$​​​​​​​ solution and for conversion of ‘C’ to ‘D’.
✓

Answer


$'A'$ = Sulphur, $'B'$ = $H_2S$ gas, $'C' = SO_2$ gas, $'D' = SO_3​​​​​​​$​​​​​​​ gas
Reactions are:

$\ \ \ \ 2\text{SO}_2\text{(g)}\ \ \ +\ \ \ \text{O}_2\text{(g)}\ \ \ \xrightarrow{\text{v}_2\text{O}_5\text{(a)}\ \ \ }\ \ 2\text{SO}_3(\text{g})\\^\text{Sulphur dioxide}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ^\text{Sulphur trioxide}\\ \ \ \ \ \ ^\text{(C)}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ^\text{(D)}$

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