Combustion

samanthaywu
Posts: 89
Joined: Wed Sep 30, 2020 9:51 pm

Combustion

How do you know when to assume the remaining reactant is O2? O2 is usually not the limiting reactant but sometimes it's not explicitly mentioned.

Shanna Yu 1C
Posts: 106
Joined: Wed Sep 30, 2020 9:36 pm
Been upvoted: 3 times

Re: Combustion

Hi!

Someone can correct me if I'm wrong, but I believe combustion problems typically operate under the assumption that oxygen is in excess unless it's stated otherwise.

Arti_Patel_3H
Posts: 107
Joined: Wed Sep 30, 2020 9:38 pm

Re: Combustion

Shanna Yu 3F wrote:Hi!

Someone can correct me if I'm wrong, but I believe combustion problems typically operate under the assumption that oxygen is in excess unless it's stated otherwise.

You're correct. Usually, it is assumed there is an excess of O2 in combustion reactions.

Sonel Raj 3I
Posts: 92
Joined: Wed Sep 30, 2020 9:48 pm

Re: Combustion

If there is no amount value given for O2, like the other replies say, you usually assume O2 is in excess in a combustion reaction. From what I have seen in this class so far, they usually tell us that the experiment is performed with an "excess of oxygen," so I don't think we have to worry about it too much!

Emily_Stenzler_2H
Posts: 196
Joined: Wed Sep 30, 2020 10:02 pm

Re: Combustion

I believe this is just something we have to memorize for this class- we just need to know the typical products and reactants for a combustion reaction, and we need to know that O2 is usually in excess.

Katie Le 3K
Posts: 73
Joined: Wed Sep 30, 2020 9:35 pm

Re: Combustion

O2 is in excess for combustion problems. i think its just something we assume unless explicitly stated otherwise

Rose_Malki_3G
Posts: 127
Joined: Wed Sep 30, 2020 10:02 pm

Re: Combustion

In general, it is usually assumed that the O2 is in excess so it would usually not be the limiting reactant.

George Hernandez 3I
Posts: 95
Joined: Wed Sep 30, 2020 9:52 pm

Re: Combustion

The problem should always tell you when an excess reactant is present in a reaction. So then you'll have to work with the limiting reactant to solve whatever it is the problem is asking. Oxygen will very typically always be in excess since it is unusual, in the real world, to run out of oxygen in an environment for a combustion reaction. However, if they give you a certain number of moles of oxygen to work with, at that point, you should use your molar ratio knowledge to figure if it's the limiting reactant in that reaction.

Edwin Liang 1I
Posts: 93
Joined: Wed Sep 30, 2020 9:34 pm

Re: Combustion

Hi,
In combustion reactions, the Oxygen is usually in excess unless its specific amount is given

tholz11
Posts: 70
Joined: Wed Sep 30, 2020 9:38 pm

Re: Combustion

In combustion reactions, Oxygen is always in excess unless stated otherwise!

Astha Patel 2J
Posts: 101
Joined: Wed Sep 30, 2020 10:03 pm
Been upvoted: 2 times

Re: Combustion

Oxygen gas can be assumed in excess during combustion reactions unless stated otherwise.