Question

When molten $AlC{l}_3$ is electrolysed with a current of 0.5 ampere to produce 27 g Al, _____ litres of Cl${}_2$ at STP are formed.

• A. 22.4
• B. 33.6
• C. 24.47
• D. 36.7
  

Answer 1

Answer: (B)

33.6

$A{l}^{3+}+3e^{-}\to Al$
$2C{l}^{-}\to C{l}_2+2e^{-}$
Equivalent of Al at cathode = Equivalent of Cl at anode
$\frac{27}{9}=\frac{w_{C{l}_2}}{35.5}$
$w_{C{l}_2}=106.5$
$n_{C{l}_2}=1.5$
We know $PV=nRT$
$V=\frac{1.5\times 0.821\times 273}{1}$
$V=33.61litres$.