Question

what is the correct coefficient for h₂o when balancing the equation ch₄ + 2o₂ → co₂ + h₂o?
a. 2
b. 1
c. 4
d. 3

Explanation:

Step1: Count hydrogen atoms on left - hand side

The reactant $CH_4$ has 4 hydrogen atoms.

Step2: Balance hydrogen atoms

To balance hydrogen atoms on the right - hand side in $H_2O$, since each $H_2O$ molecule has 2 hydrogen atoms, we need 2 $H_2O$ molecules to get 4 hydrogen atoms.

Answer:

A. 2