How to Balance Equations in Stoichiometry Problems


Hi, I'm Rachel, and today we're going to be going over how to balance equations in stoichiometry problems. So, if you're taking chemistry and you want to add up reactants and products, you're going to have to make sure to balance them. Here we have nitrogen, which is a gas, plus hydrogen, which is also a gas, and then we do an arrow to show the reactants, and nitrogen and hydrogen can give us ammonium, which is also a gas, so a little g. Now, we have to balance this equation. When you're balancing, always do the other elements before you look at hydrogen and oxygen. So remember O and H last. So, we're going to start off with nitrogen, because hydrogen we want to do last. Now we want to remember that we have the same nitrogen on the reactant side as we do on the product side. So here we have two nitrogen, right? Because it's N2, and here we only have one nitrogen, because there's a one coefficient because there's nothing written there. So, two on this side, one on this side, we're gonna have to add the coefficient two in front of the n to get two nitrogen on this side. So now we have two nitrogen here and three nitrogen here, so great, our nitrogen is balanced. Now let's look at the hydrogen because there's nothing else to do and that's the last term we want to look at. Here you can see we have three hydrogen but we added a coefficient two in front of it, so that gives us actually six hydrogen, whereas here we only have two hydrogen. So, if we put a three in front here, and we multiply three and two we get six. So now we have six hydrogen on both sides. So that's two nitrogens on both sides, six hydrogen on both side, so we see that it's balanced, and we've balanced the equation. I'm Rachel, and thank you for learning with me today.

Rachel Kaplove has worked as a professional private tutor since 2005. Specializing in Math and Science, she tutors students from the second grade level to advanced high school honors levels.