## Need help w/ determining the moles of gas produced

KylieY_3B
Posts: 31
Joined: Fri Sep 28, 2018 12:24 am

### Need help w/ determining the moles of gas produced

Could someone explain how to find the net number of moles of gas produced for number 19 on the second review module?

It involves the combustion of 4 moles of butane (C4H10) gas. I understand how to balance the equation but I'm unsure how to determine the net number of moles of gas produced. The possible answers are 6, 4, and 5.

Brandon_Tran_2E
Posts: 63
Joined: Fri Sep 28, 2018 12:23 am

### Re: Need help w/ determining the moles of gas produced

Hey Kylie, the net moles of gas means the overall moles gas produced from the reactants. There are 36 moles on the product side and 30 moles on the reactant side. The net change is 36 - 30 = 6

Hai-Lin Yeh 1J
Posts: 89
Joined: Fri Sep 28, 2018 12:16 am
Been upvoted: 1 time

### Re: Need help w/ determining the moles of gas produced

The chemical equation is:
4 C4H10 (g) + 26O2 (g) -> 16 CO2 (g) + 20 H2O (g)

You can find the net number of moles produced by looking at the stoichiometric coefficients.
You take the sum of coefficient of product and minus sum of coefficient of reactants to get the net number of moles produced.
4+ 26 = 30 moles of reactants produced.
16 + 20 = 36 moles of products produced.
36 - 30 = 6.