C7H6O2 + O2 → CO2 + H2O
can someone show me step by step how do balance that

2C7H6O2 + 15O2 → 14CO2 + 6H2O  

Explanation:

C7H6O2 + O2 → CO2 + H2O

Carbon is not balanced (Reactant - 7, Product - 1)

Adding 7 to CO2;

C7H6O2 + O2 → 7 CO2 + H2O

Carbon is now balanced, however hydrogen is not balanced (Reactant - 6, Product - 3)

Adding 3 to H2O;

C7H6O2 + O2 → 7 CO2 + 3 H2O

Hydrogen is now balanced, however oxygen is not balanced (Reactant - 4, Product - 3)

Since 3H2O gives an odd value of O, multiply all through by 2;

2C7H6O2 + 2O2 → 14 CO2 + 6 H2O

Oxygen is still not balanced (Reactant - 8, Product - 34)

Change 2O2  to 15O2;

2C7H6O2 + 15O2 → 14CO2 + 6H2O  

Equation is now balanced.

i look it up online and i'll tell you

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