A compound containg 3 atoms of carbon and 8 atoms of hydrogen is combined in a reaction with oxygen molecules. The two end products of this equation are carbon dioxide (CO2) and water. What element should you look at first in balancing this equation?

Answer 1

C3H8 + O2 ==> CO2 + H2O.
In my mind there is no "first" element to look at in balancing. People balance equations different ways. However, in the spirit of the question, I would start with C.

Answer 2

Oxigeno