Question

What is the correct way to balance this equation?

H2 + O2→H2O

Responses

2H2 + O2→2H2O

2 uppercase H subscript 2 end subscript plus uppercase O subscript 2 end subscript rightwards arrow 2 uppercase H subscript 2 end subscript uppercase O

H2 + 2O2→H2O

uppercase H subscript 2 end subscript plus 2 uppercase O subscript 2 end subscript rightwards arrow uppercase H subscript 2 end subscript uppercase O

H2 + O→H2O

uppercase H subscript 2 end subscript plus uppercase O rightwards arrow uppercase H subscript 2 end subscript uppercase O

2H2 + O2→H2O

Answer 1

The correct balanced equation is:

2H2 + O2 → 2H2O

Check by counting atoms: left side H = 4, O = 2; right side H = 4, O = 2. (You could also write H2 + 1/2 O2 → H2O, but integer coefficients are preferred.)