Answer:
Benzoic acid and oxygen.
Water and carbondioxide gas.
carbon.
Explanation:
The two reactants of the chemical reaction are benzoic acid and oxygen whereas the two products of this chemical reaction are water and carbondioxide gas. The unknown substance must contains carbon in its composition. When the benzoic acid react with the oxygen gas, it produces two products i.e. water and carbondioxide gas. These two products are formed from the combustion of benzoic acid in the presence of oxygen gas.