Consider the following intermediate chemical equations 2h2(g 200 h2(g)+f2(g) → 2hf(g) in the final chemical equation, hf and o2 are the products that are formed through the reaction between h2o and f. before you can add these intermediate chemical equations, you need to alter them by multiplying the second equation by 2 and reversing the first equation. first equation by 2 and reversing it. first equation by (1/2) and reversing the second equation. second equation by 2 and reversing it.