Question

What is the reactant in the following equation?

Answer 1

To remember what the reactant is, it always comes before the yielding sign (arrow). The elements after the arrow are known as the 'products'.
So, with this information, let's look for our reactants.
Remember, the reactants are the elements BEFORE the yielding sign (arrow).
We have Hydrogen and Oxygen before the arrow.

Your answer is:
Hydrogen + Oxygen

I hope this helps!