Balance the equation for the reaction of benzene and hydrogen to form cyclohexane.. c6h6 + h2 → c6h12.

Here is a universal law to balance chemical equations :
All chemical equations must be balanced because of the law of conservation of mass.
It states that "matter cannot be created or destroyed."
So, the number of atoms that you start with at the beginning of the reaction must equal the number of atoms that you end up with.
 keeping this law in our mind,lets balance the equation for the reaction of benzene and hydrogen to form cyclohexane.
C 6 H 6 + H 2 → C 6 H 12.
Here is the balance chemical equation.
2 C 6 H 6 + 6 H 2 → 2 C 6 H 12.