[pepper_mix_salt]

hi please *delete me*
(:
this is a question related to stoichoimetry.

15cm3 of a mixture of CO and CH4 was mixed with excess O2 and exploded. there was a contraction in volume of 21cm3 at room temperature and pressure. what is the percentage by volume of CH4 in the mixture?

do i separate the CO and CH4 separately when i form equations with O2 or do i combine them? im confused.
thank you very much.

[AWK]

Write down balanced equations for 1 mole of each compound separately, eg:

C₂H₆ + 3.5O₂ = 2CO₂ + 3H₂O

Treat water as removed completely (this usually gives an error of ~3%).

Set a system of 2 equation with 2 variables (volumes of CO and CH₄)