Question

Find the oxidation number of sulphur for the given coumpound.

• A. $+4$
• B. $+6$
• C. $+2$
• D. $+5$

Answer 1

The correct option is A $+4$

Valency of each oxygen which is having single bond with sulphur will be considered as -1 and which is having double bond will be considered -2.
We can see molecule overall is neutral.

Let the oxidation number of sulphur which is bonded with 3 oxygens is $x$.
$\Rightarrow x+1\times (-1)+2\times (-2)=0$
$\Rightarrow x=+5$

Let the oxidation number of sulphur which is bonded with 2 oxygens is $y$.
$\Rightarrow y+1\times (-1)+1\times (-2)=0$
$\Rightarrow y=+3$

Average oxidation state of sulphur= $\frac{x+y}{2}=+4$

Thus, Average oxidation state of sulphur is $+4$.