[excal]

Electrolysis can be used to determine atomic masses. A current of 0.450A deposits 0.786g of a certain metal in 50.0 minutes. calculate the atomic mass of the metal if n= 2. Identify the metal.

I think n = mol, therefore there is 2 mole of the metal per mole of electron.

0.450A x 3000s = 1350 C

To find moles of electron, 1350C * 1 mol e/96500C = 0.01399 moles of electron

Multiplied by two, you get 0.02798 moles of this metal.

0.02798 * x g / mol = 0.786g
x g = 0.786g / 0.02798
x = 28.09g

That's not one of the 5 choices for answers on my assignment though. It was a) 91.2, b) 47.9, c) 200.6, d) 65.4, or e) 112.4

Anyone care to point out where I gone wrong? thanks in advance.

[Borek]

there is 2 mole of the metal per mole of electron.

You mean half electron per reduced metal atom?

[chiralic]

Check this link:


http://members.aol.com/logan20/faraday.html, Look at on The Laws of Electrolysis...

Regards,

Chiralic