C6H5COOH + O2 = CO2 + H2O plz tell me the steps how to balance this. The answer of this is :  2 C₆H₅COOH + 15 O₂ = 14 CO₂ + 6 H₂O

Hi,

The balanced equation can be shown as:

2C₆H₅COOH + 15 O₂ → 14 CO₂ + 6 H₂O

The way to balance this equation is hit and trial method. First balance the carbon atoms that will make 7 carbon each side by multiplying CO₂ by 7,

C₆H₅COOH +  O₂ → 7 CO₂ +  H₂O

Now balance the hydrogen atoms, they are 2 on RHS and 6 on LHS, thus multiply RHS by 3

C₆H₅COOH + O₂ → 7 CO₂ +  3H₂O

Now we have 17 oxygen on RHS 4 on LHS. keeping the number of oxygen atoms same in C₆H₅COOH, multiply oxygen atoms on LHS by 15/2

C₆H₅COOH + 15/2O₂ → 7 CO₂  +   3H₂O

Thus this on multiplying gives

2C₆H₅COOH + 15 O₂ → 14 CO₂ + 6 H₂O

Hope it helps.

Cheers!