Question

$Na{H}_2\underset{–}{P}{O}_4$
What will be the oxidation state of underlined element?

• A. $+5$
• B. $+3$
• C. $-3$
• D. $-5$

Answer 1

The correct option is A $+5$

Let, oxidation state of $P$ be $x$ in $Na{H}_2\underset{–}{P}{O}_4$.
Oxidation number of $Na=+1$
Oxidation number of $H=+1$
Oxidation number of $O=-2$
$+1+(+1\times 2)+x+(4\times -2)=0$
$+1+2+x-8=0$
$x+3-8=0$
$x=+5$