`Al_(2)O_(3)` is reduced by electrolysis at low potentials and high currents. If `4.0xx10^(4)` amperes of current is passed through molten `Al_(2)O_(3)` for 6 hours, what mass of aluminium is produced ? (Assume 100% current efficiency, atomic mass of `Al=27` g/mol)

Options

A. `8.1xx10^(4)g`
B. `2.4 xx 10^(5)g`
C. `1.3xx10^(4)g`
D. `9.0xx10^(3)g`

Answer

A

Explanation

`Al^(3+)+3e^(-) rarr Al`
Quantity of electricity passed
`=Ixxt=4xx10^(4)xx6xx3600`
`=8.64xx10^(8)C`
`3xx96500C` of electricity deposit `Al=27g`
`8.64xx10^(8)C` of electricity will deposit Al
`=(27)/(3xx96500)xx8.64xx10^(8)=8.16xx10^(4)g`