Unit 4, Lesson 25

In order to determine the mass of product produced by a certain mass of reactant (and vice versa), it is necessary to convert mass to moles and then back to mass. This process is called "the mole tunnel". The balanced chemical equations are written in moles--how is that known? Because the coefficients represent the number of moles of reactant. Sometimes a problem tells us how many grams of each reactant we have, and we have to find the mass of the precipitate or product. Sometimes, we know the mass of the product, and we have to find the mass of one of the reactants. This is where I, and a lot of others, found out that stoichiometry isn't all that easy!

Practice Problems: