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Moles

Hi, I asked my teacher this today and she was unable to give me an answer. Why is it when 1 mole of a substance reacts with 2 moles of a substance, only one mole is produced. (Our example was Ca(OH)2 where 1 mole of Ca reacts with 2 moles of OH to produce 1 mole of Ca(OH)2).
Thanks.

Reply 1

Ishaan_

Original post

by matthew.reynolds

think of it in terms of oxidation states? (idk if you have done those so just in case I will use a gcse explanation).
As you should know Calcium is 2+ therefore in order to form calcium hydroxide, we need a negative charge of -2 to cancel out with the +2 of the calcium. Therefore, we have Ca(OH)2 and this molecule is neutral. Hope that helps!