Connie and Dwayne know the solid potassium reacts very strongly with water producing a chemical called potassium hydroxide along with hydrogen gas. They know the chemical equation looks like this

Question

2k + 2H2O---->2KOH + some amount of H2
There are 4 atoms of hydrogen shown on the reactants side. How many total atoms of hydrogen must be on the product side
2
4
6
8

Answer 1

On the reactants side, there are 2 water molecules, which means there are 4 hydrogen atoms. Looking at the product side, the chemical equation shows that 2 molecules of potassium hydroxide (KOH) are formed. Each molecule of KOH contains 1 hydrogen atom. Therefore, on the product side, there are a total of 2 x 1 = 2 hydrogen atoms.

So, the correct answer is 2.