In the second experiment, another flask is used for a combustion reaction.
Method
Remove all the air from the flask.
Add 0.0010 mol of 2,2,4-trimethylpentane (CaHi) to the flask.
Add 0.0200 mol of oxygen to the flask.
Spark the mixture to ensure complete combustion.
Cool the mixture to the original temperature.
The equation is
C8H18(g) + 12.5O2(g) ——> 8 CO2(g) + 9 H20(l)
Calculate the amount, in moles, of gas in the flask after the reaction.
The answer is 0.0155 mol
M1 amount of CO2 formed in flask = 0.008 mol
Allow ECF from M1 to M2
M2 amount of gas in flask
= 0.0075 (O2) + 0.0080 (M1) = 0.0155 mol
I get M1 but the second part I don’t understand where the 0.0075 comes from Ik it says oxygen in brackets but O2 value is 0.0200mol and why would there be oxygen after the reaction anyway cuz in the equation only carbon dioxide and water is left. Someone please explain thank youu