Question

How can you find a limiting reactant using moles?

Answer 1

For this you just have to watch the balanced equation of the reaction.

Explanation:

For eg:

`"N"_2 + 3"H"_2 -> 2"NH"_3`

This means that `1` mole of `"N"_2` reacts with `3` moles of `"H"_2` and makes `2` moles of `"NH"_3`.

If you are given `5` moles of `"N"_2` and `9` moles of `"H"_2`, then what's the limiting reagent?

You can find it here

`"1 mole N"_2` `"reacts with 3 moles H"_2`

`"2 moles N"_2` `"react with 6 moles H"_2`

`"3 moles N"_2` `"react with 9 moles H"_2`

Oh see!! The `"H"_2` moles are consumed when `3` moles of `"N"_2` react. But you have `5` moles of `"N"_2` available, so in this case, `"H"_2` is the limiting reagent.

Hope you understand.