Question

When chlorine reacts with dil. $NaOH$ under cold conditions, the oxidation state of chlorine changes from zero to

• A. - 1 and + 5
• B. + 1 and + 4
• C. + 5 and +3
• D. - 1 and + 1

Answer 1

Answer: (D)

When chlorine reacts with dilute and cold $NaOH$, sodium chloride and sodium hypochloride are formed.
$2NaOH$ (cold) $+C{l}_2\to NaCl+\underset{\text{soldium hypochloride}}{\mathrm{NaClO}}+H_{2}O$
Let oxidation state of $Cl$ in $NaCl$ is $x$.
$NaCl+1+x=0x=-1$
Let oxidation state of $Cl$ in
$NaClO$ is $x.NaClO$
$+1+x-2=0$
$x-1=0$
$x=+1$
$\therefore$ Oxidation states of chlorine changes from
$0$ to $-1$ and $+1.$