Question

A Compound Containing 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 And Water. What Element Should You Look At First In Balancing This Equation?

Answer 1

C3H8 + n O2 -> 3CO2 + 4H2O is the reaction. That results from the number of H and C atoms in the C3H8, and the products they tell you exist.

To balance it, use the fact that
2n = 10
which is based upon the number of O atoms in the reaction.

Answer 2

Carbon