$9.65 \ C$ of electric current is passed through fused anhydrous $MgCl_2$. The magnesium metal thus obtained is completely converted into a Grignard reagent. The number of moles of Grignard reagent obtained is

The number of moles of electrons required to deposit $36 \ g$ of $Al$ from an aqueous solution of $Al(NO_3)_3$ is (At. wt. of $Al = 27$)

The approximate time duration in hours to electroplate $30 \ g$ of calcium from molten calcium chloride using a current of $5 \ A$ is [At. mass of $Ca=40$]

$A$ current of $10.0 \, A$ flows for $2.00 \, h$ through an electrolytic cell containing a molten salt of metal $X$. This results in the decomposition of $0.250 \, mol$ of metal $X$ at the cathode. The oxidation state of $X$ in the molten salt is $(F = 96,500 \, C \, mol^{-1})$ (in $+$)

Which is the weight of $Al$ deposited at cathode when $1 \ A$ current is passed through molten $AlCl_3$ for $9650 \ s$ (in $g$)?
(Atomic mass of $Al = 27$)

Salts of $A, B$ and $C$ were electrolysed under identical conditions using the same quantity of electricity. It was found that when $2.1 \ g$ of $A$ was deposited,the weights of $B$ and $C$ deposited were $2.7 \ g$ and $9.6 \ g$. If the atomic mass of $A, B$ and $C$ are $7, 27$ and $64$ respectively,then the valencies of $A, B$ and $C$ respectively are: