Solving a chemistry problem

Solving a chemistry problem

6. 100 ml of a mixture of hydrogen, methane and oxygen was burned in the eudiometer. After condensation of water vapor and bringing the gas to the initial conditions, the volume of the resulting mixture was 35 ml. After absorption of carbon dioxide by alkali, the volume of the residue is 25 ml. Determine the composition of the mixture taken if the remaining smoldering splinter lights up.

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