Question

1ch₄ + 2o₂ → 1co₂ + 2h₂o
elements total # before (reactants) total # after (products)
c
h
o
this chemical reaction is balanced. true false

Explanation:

Step1: Count carbon atoms

In reactants, in $CH_4$ there is 1 C atom. In products, in $CO_2$ there is 1 C atom.

Step2: Count hydrogen atoms

In reactants, in $CH_4$ there are 4 H atoms. In products, in $2H_2O$ there are $2\times2 = 4$ H atoms.

Step3: Count oxygen atoms

In reactants, in $2O_2$ there are $2\times2=4$ O atoms. In products, in $CO_2$ there are 2 O atoms and in $2H_2O$ there are 2 O atoms, total $2 + 2=4$ O atoms.

Answer:

Elements	Total # Before (reactants)	Total # After (Products)
H	4	4
O	4	4

True