Question

What is the maximum number of moles of `KClO_3` that could form in the combination of 6.0 moles of `Cl_2` with 9.0 moles of `KOH`?

Answer 1

9.0

Explanation:

First, write out and balance the chemical reaction.

`Cl_2 + 2KOH → 2KClO_3 + H_2` (redox reaction, Cl is reduced, H is oxidized)

NOW we can see that 1 mole of `Cl_2` requires 2 moles of KOH for a complete reaction. This means that complete reaction of our 6.0 moles of `Cl_2` would require 12.0 moles of KOH. We don’t have that much, so KOH is the “limiting reagent”.

Working it back the other way, 9.0 moles of KOH will react completely with 4.5 moles of `Cl_2`. This reaction will produce 9.0 moles of the product because one mole of product is produced for every mole of KOH reacted.