Question

Which is the best description of the behaviour of bromine in the reaction given below?
$H_{2}O+B{r}_2\to HOBr+HBr$

• A. Proton acceptor only
• B. Both oxidised and reduced
• C. Oxidised only
• D. Reduced only

Answer 1

The correct option is B Both oxidised and reduced

$H_{2}O+\stackrel{0}{B{r}_2}\to HO\stackrel{+1}{Br}+H\stackrel{-1}{B}r$
In the above reaction, the oxidation number of $B{r}_2$ increases from zero (in $B{r}_2$) to $+1$ (in $HOBr$) and decreases from zero (in $B{r}_2$) to $–1$ (in $HBr$). Thus, $B{r}_2$ is oxidised as well as reduced and hence, it is a redox reaction.