Balance the equation C4H8 + O2 ->CO2 + H2O
C4H8 + O2 -> CO2 + H2O
Want to deal with only one element at the time, recap that you can only add coefficients to the front of chemical formulae, you cannot change the little numbers (number of atoms of that element within the molecule)First look at carbon atoms in the most complex molecule- four on the left hand side and one on the right. Put 4 in front of CO2 to balance theseThen move to hydrogen, there are currently 8 on the left hand side and only two on the right, so we multiply H2O by 4 to make 8 hydrogen atoms. Put 4 in from of H2O.Finally we have to consider how multiplying has affected the number of oxygen atoms in our equation. Placing a 4 in front of CO2 created 8 oxygen atoms on the right, and placing 4 in front of H2O has added 4 oxygen atoms to the right also, making 12 oxygen atoms in total, as oxygen is a diatomic molecule (O2) we therefore need 6 in front of O2 in order to balance this equation (2x6=12)
Overall C4H8 + 6O2 -> 4CO2 + 4H2O
