Question

How many minutes will it take to plate out 16.22 g of aluminum metal from a solution of Al³⁺ using a current of 12.9 amps in an electrolytic cell?

		60.1
		13480
		173
		74.9
		225

Answer 1

Answer – We are given, mass of Al = 16.22 g, current = 12.9 A

First we need to calculate the moles of Al

Moles of Al = 16.22 g / 26.982 g.mol^-1

                    = 0.601 moles

We know 1 moles of Al given 3 moles of electrons

Al ------> Al³⁺ + 3 e^-

So, 1 moles of Al = 3 moles of e^-

So, 0.601 moles of Al = ?

= 1.80 moles of electrons

We know

1 moles of electron = 96485 C

So, 1.80 moles of electron = >

= 174003.4 C

We know

Electric charge = current (A) * time (s)

So, time = Electric charge(C) / current (A)

               = 174003.4 C / 12.9 A

               = 13488.6 s

We know

60 s = 1 min

So, 13488.6 s = ?

= 224.8 min

= 225 min

So, 225 minutes will it take to plate out 16.22 g of aluminum metal from a solution of Al³⁺ using a current of 12.9 amps in an electrolytic cell