Question

$C{l}_2$ gas is obtained by various reactions but not by:

• A. $KMn{O}_4+\text{conc.}HCl\stackrel{\Delta }{\to }$
• B. $KCl+K_{2}C{r}_2{O}_7+\text{conc.}{H}_{2}S{O}_4\stackrel{\Delta }{\to }$
• C. $Mn{O}_2+\text{conc.}HCl\stackrel{\Delta }{\to }$
• D. $KCl+F_2\to$

Answer 1

The correct option is B $KCl+K_{2}C{r}_2{O}_7+\text{conc.}{H}_{2}S{O}_4\stackrel{\Delta }{\to }$

a) $2Mn{O}_4^{-}+16H^{+}+10C{l}^{-}\to 2M{n}^{2+}+8H_{2}O+5C{l}_2$
b) Chromyl chlordie test; $C{r}_2{O}_7^{2-}+4C{l}^{-}+6H^{+}\to 2Cr{O}_{2}C{l}_2\uparrow \left(\text{deep red}\right)+3H_{2}O$
c) $Mn{O}_2+4HCl\to MnC{l}_2+C{l}_2+2H_{2}O$
d) $2C{l}^{-}+F_2\to C{l}_2+2F^{-}$
Except (b), all the other reactions are oxidation reactions and gives $C{l}_2$