Question

The correct sequence of the oxidation state of underlined elements is
$N{a}_2\left[\frac{Fe}{}{\left(CN\right)}_{5}NO\right]$, $K_2\frac{Ta}{}{F}_7$, $M{g}_2{P}_2{O}_7$, $N{a}_2\frac{S_4}{}{O}_6$, $\frac{N_3}{}H$

• A. $+3$, $+5$, $+5$, $+2.5$, $-\frac{1}{3}$
• B. $+5$, $+3$, $+5$, $+3$, $+\frac{1}{3}$
• C. $+3$, $+3$, $+5$, $+5$, $-\frac{1}{3}$
• D. $+5$, $+5$, $+3$, $+2.5$ $+\frac{1}{3}$

Answer 1

Answer: (A)

$N{a}_2\left[Fe{\left(CN\right)}_{5}NO\right]:+2+x+5\left(-1\right)+0=0$
$\Rightarrow x=+3$
$K_2\frac{Ta}{}{F}_7:+2+x+\left(-7\right)=0\Rightarrow x=+5$
$M{g}_2{P}_2{O}_7:+4+2x+\left(-14\right)=0\Rightarrow x=+5$
$N{a}_2\frac{S_4}{}{O}_6:+2+4x+\left(-12\right)=0$ or $4x=10\Rightarrow x=+2.5$
$\frac{N_3}{}H:3x+1=0\Rightarrow x=-\frac{1}{3}$