question_answer

In the following reaction sequence in aqueous solution, the species X, Y and Z are, respectively,

A) X - \[N{{a}_{2}}S{{O}_{3}}\] Y - \[Cu{{S}_{2}}{{O}_{3}}\] Z - \[N{{a}_{2}}[C{{u}_{5}}{{({{S}_{2}}{{O}_{3}})}_{6}}]\]

B) X - \[N{{a}_{2}}{{S}_{4}}{{O}_{6}}\]          Y - \[C{{u}_{2}}({{S}_{2}}{{O}_{3}})\]        Z - \[N{{a}_{4}}[C{{u}_{6}}{{({{S}_{2}}{{O}_{3}})}_{5}}]\]

C) X - \[N{{a}_{2}}S{{O}_{4}}\] Y - \[Cu{{S}_{4}}{{O}_{6}}\] Z - \[N{{a}_{3}}[C{{u}_{5}}{{({{S}_{2}}{{O}_{3}})}_{4}}]\]

D) X - \[NaHS{{O}_{4}}\]            Y - \[C{{u}_{2}}({{S}_{4}}{{O}_{6}})\]        Z - \[Na[C{{u}_{3}}{{({{S}_{2}}{{O}_{3}})}_{2}}]\]

Correct Answer: B

Solution :

[b] (i) \[2Cu{{(N{{O}_{3}})}_{2}}+2N{{a}_{2}}{{S}_{2}}{{O}_{3}}\xrightarrow{{}}C{{u}_{2}}{{(N{{O}_{3}})}_{2}}+2NaN{{O}_{3}}+\underset{(X)}{\mathop{N{{a}_{2}}{{S}_{4}}{{O}_{6}}}}\,\](ii)

4	6	5
\[N{{a}^{+1}}\]	\[C{{u}^{+1}}\]	\[{{S}_{2}}{{O}_{3}}^{-2}\]