An aqueous solution of a crystalline salt reacts with dilute \(HCl\) to give a yellow precipitate and a gas that turned dichloromate paper green. The crystalline salt may be, ____________
A. \(Na _{2} S _{2} O _{3} \cdot 5 H _{2} O\) B. \(Na _{2} CO _{3} \cdot 10 H _{2} O \) C . Na _{2} S\) C. \(NaHCO _{3}\)
Correct Answer: A
Explanation
The cquation of the reaction $$ Na _{2} S _{2} O _{3} .5 H _{2} O _{( iv }+2 HCl _{(24)} \rightarrow 2 NaCl _{(a+1)}+6 H _{2} O _{(n)}+ SO _{24 p}+ S _{(0)} $$
