Question

Molten $AlC{l}_3$ is electrolysed with a current of 0.5 ampere to produce $27$ g $Al.$ How many g-equivalent of $Al$ are formed?

Answer 1

$27$ g of $Al$ corresponds to $1$ mole as the molecular weight of $Al$ is $27$ g/mol.
$A{l}^{3+}+3e^{-}\to Al$
Thus $3$ electrons will deposit $1$ mole of $Al.$$Hence,theequivalentmassof$Al$is$=\dfrac {27}{3}=9$Hence,thenumberofgramequivalentsin$27 g$of$Al$is$\dfrac {27}{9}=3.$Thus,$3$gramequivalentsof$Al$ will be deposited.