I'm assuming that you are asking a general question because you did not include an example.
The limiting reagent is the item in the reactants (reagents) that will run out first. This is because it limits what the reaction can produce, essentially causing the leftover elements/compounds to just sit there.
Answer:
The answer is Ionization energy.
Explanation:
Ionization Energy. The ionization energy tends to increase as one moves from left to right across a given period or up a group in the periodic table.
Moles of electrons:
The moles of electrons that are transferred are 12F
A balanced equation:
2 moles of Aluminium metal react with excess copper(II) nitrate.

Given:
Moles of Aluminium = 2
As Aluminium goes from 0 to +3 oxidation state

And copper goes from +2 to 0

On balancing the number of electrons we get:
For 1 mole of Al
is required.
Therefore for 2 moles of Al,
Total
F mole of electrons
Where F= Faraday's constant= 96500 C
So, 12F moles of electrons are transferred.
Learn more about Faraday's Law here,
brainly.com/question/27985929
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