P-Block Elements Ques 501
Question: Sulphur in +3 oxidation state is present in
[DCE 2003]
Options:
A) Sulphurous acid
B) Pyrosulphuric acid
C) Dithionous acid
D) Thiosulphuric acid
Show Answer
Answer:
Correct Answer: C
Solution:
Dithionous acid $ (H_2S_2O_4) $ has sulphur in +3 oxidation state. $ HO-\overset{O}{\mathop{\overset{||}{\mathop{S}}}}-\overset{O}{\mathop{\overset{||}{\mathop{S}}}}-OH $ ; $ 2(+1)+2x+4(-2)=0 $ $ 2x=8-2=6 $ ; $ \overset{+4}{\mathop{MnO_2}}+4HCl\to \overset{+2}{\mathop{MnCl_2}}+2H_2O+Cl_2 $
