Relationship between moles of O2 and Ch2 Units in a combustion reaction

[deezer]

Homework Statement

I want to find a relationship between the number of moles of O2 used and the number of CH2 units in an alkane in a complete combustion reaction.

Homework Equations

The Attempt at a Solution

Right now I have come up with a math equation, given X units of CH2, to find the number of O2 moles. I used patterns to find the equation, is there any other relationship? The more units of CH2 you have, the more O2 you need to combust it right?

 

[epenguin]

This is very very elementary but just give a chemical equation if you want help although you seem to say you have solved it.

 

[deezer]

It was a generic question, I'm only concerned that I am not thinking outside of the box by considering only the mathematical relationship.

 

[epenguin]

Until you write down what your actual thoughts are, preferably in some sort of formula or calculation, we do not know what you mean.

 

[DeeNos]

I would like to clarify and provide some additional information about the relationship between moles of O2 and CH2 units in a combustion reaction.

Firstly, it is important to note that the number of CH2 units in an alkane molecule will vary depending on the specific alkane being used. For example, methane (CH4) has one CH2 unit, while octane (C8H18) has eight CH2 units. Therefore, the relationship between moles of O2 and CH2 units will also vary depending on the alkane being used.

Additionally, in a complete combustion reaction, the reactants (in this case, O2 and the alkane) will be completely consumed, resulting in the formation of carbon dioxide (CO2) and water (H2O). The balanced chemical equation for a complete combustion reaction of an alkane can be represented as:

CnH2n+2 + (3n+1/2)O2 → nCO2 + (n+1)H2O

From this equation, we can see that the number of moles of O2 needed is directly proportional to the number of CH2 units in the alkane being combusted. For example, if we have one mole of methane (CH4), we would need one mole of O2 to completely combust it. On the other hand, if we have one mole of octane (C8H18), we would need 25 moles of O2 to completely combust it.

In summary, the relationship between moles of O2 and CH2 units in a combustion reaction is directly proportional, with the specific ratio being determined by the balanced chemical equation for the combustion of the specific alkane being used. I hope this clarifies the relationship between these two variables.