[Ilikebugs]

Which of the following produces the greatest mass of metal upon reduction with one mole of electrons?
A Al3+
B Cu2+
C Pt2+
D Mg2+
E Ag+

I don't know where to start with this, I read online about reducing agents and oxidization numbers but I don't understand how to get masses.

[Borek]

How many moles of each will be reduced by one mole of electrons?

[Ilikebugs]

The smallest positive charge will be able to have the most ions be reduced as it only needs 1 electron per ion compared to 2 or 3?

[Borek]

Yes, but that's just only part of the answer.

Which weighs more: mole of sodium, or half mole of platinum?

[Ilikebugs]

A half mole of platinum? When I look at the answer sheet it says Ag is the answer

[Borek]

A half mole of platinum?

Yes. Now use the same approach to calculate mass for each case.

When I look at the answer sheet it says Ag is the answer

Where did I wrote half mole of platinum is the right answer? I was just pointing you the right method. Sodium is not even on the list.

[Ilikebugs]

OK, so I have to find the amount of moles of ions for each element and then multiply it by their molar mass, and the largest mass produced is Ag with ~108g.