Question

how many coulombs are required to produce 54 gram of Al from molten Al2O3​

Answer 1

Answer: 579000 C

Explanation:

Mass of Al = 54 g

The molecular mass of Al = 27 g/mol

∴ No. of moles in 54 g of Al  = 54/27 = 2 moles

Let’s write a balanced half-reaction,

Al³⁺ + 3e⁻ → Al  

From the above reaction we can conclude that,

For every 1 mole of Al, we require to produce = 3 * 96500 Coulombs of  charge

Thus,  

The required coulombs for 2 moles of Al = 3 * 96500 * 2 = 579000 C.