## Calculating Molar Mass in Limiting Reactant Problem

Daisylookinland
Posts: 46
Joined: Fri Sep 28, 2018 12:28 am

### Calculating Molar Mass in Limiting Reactant Problem

In Prof. Lavelle's lecture notes on how to find limiting reactants, he said in step 3 to calculate the molar mass of each reactant and product. However in the example he gave us he only calculated the molar mass for one of the products and not the other. Why is this?

Samantha Hoegl Roy 2C
Posts: 81
Joined: Fri Sep 28, 2018 12:15 am

### Re: Calculating Molar Mass in Limiting Reactant Problem

can you be more specific? are you talking about the CaC2 + 2H2O --> Ca(OH)2 + C2H2 example? :)

jguiman4H
Posts: 31
Joined: Fri Sep 28, 2018 12:29 am

### Re: Calculating Molar Mass in Limiting Reactant Problem

It looks like you are talking about the CaC2 + 2H20 --> Ca(OH)2 + C2H2 problem.

In class, he calculated the molar mass of C2H2 but not Ca(OH)2.

He didn't calculate the molar mass of calcium hydroxide (Ca(OH)2) because it's not relevant to answering the question. Certainly, for purposes of completeness, you could calculate its molar mass. But to answer the question, you don't need to find its molar mass as you can find limiting reactant and the theoretical yield of ethyne (both things the question was asking for) without doing so.

Hope this helps!

Manas Jinka
Posts: 32
Joined: Fri Sep 28, 2018 12:26 am

### Re: Calculating Molar Mass in Limiting Reactant Problem

The final question dealt with calculating the yield of ethyne. Thus, there is no need to calculate the molar mass of calcium hydroxide.