Question

How are mole ratios derived from balance equations?

Answer 1

From the stoichiometric coefficients of the given equation.

Explanation:

So you have the got the equation, and mass and charge are balanced, as they must be if the reaction reflects physical reality:

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

The mole ration simply follows the ratio of the stoichiometric coefficients: `1:2:1:2`, i.e. `16*g` methane is oxidized by `64*g` of dioxygen to `44*g` of carbon, and `36*g` of water. Mass and charge are balanced.....................

[And see this old question.](https://socratic.org/questions/can-you-explain-balancing-chemical-equations-in-detail#365584)