Question

In methane combustion, if `2.5*mol` `O_2` were present, what molar quantity of methane would react?

Answer 1

`CH_4(g) + 2O_2(g) rarr CO_2(g) + 2H_2O(g)`. So `1.25` `mol` methane are necessary for the given quantity of dioxygen.

Explanation:

`CH_4(g) + 2O_2(g) rarr CO_2(g) + 2H_2O(g)`.

This equation clearly tells us that each mole of methane requires 2 mole of dioxygen for complete combustion. There are `2.5` `mol` `O_2`; if complete combustion occurred, then `1.25` `mol` methane gas were combusted.