In mass-mass problems, the mass of one substance is given, and the mass of the second substance is determined from the same reaction. There are two methods for solving such types of problems:

In this type of stoichiometric calculation, the mass of one substance is determined from the given mass of the other substance using the following steps.

Step 1: Write the balanced chemical equation.

Step 2: Place the given mass above the corresponding formula, and x above the formula of the substance whose mass is to be determined.

Step 3: Write the total molar mass of the substances below the formula of each substance. (Total molar mass is the molar mass of the substance multiplied by its coefficient).

Step 4: Set up the proportion.

Step 5: Solve for the unknown mass, x.

Mole–Mole problems

Follow the steps given below to solve problems of mass-mass relationships by the mole ratio method:

Step 1: Write the balanced chemical equation.

Step 2: Convert the given mass to moles and write the obtained moles and the required quantity, x, above the formulas of the respective substances.

Step 3: Place the coefficients as the number of moles under the formula of each substance involved.

Step 4: Set up the proportion.

Step 5: Solve for the unknown value, x; and convert the moles obtained into mass.