Molar mass is the sum of all of the atomic masses in a formula. Once you determine the molar mass of a substance, it will be easy to measure out one mole of that substance.
Here are the steps to get the molar mass of the compound BaSO4 (Barium Sulfate):
1. Make a list of each element and the number of atoms of each element present in the substance.
Ba - 1
S - 1
O - 4
2. Go to the periodic table and determine the atomic mass average (atomic weight) of each element.
Ba - 137.327
S - 32.066
O - 15.9994
3. Multiply each atomic mass by the number of atoms in the formula.
Ba - 137.327 * 1 = 137.327
S - 32.066 * 1 = 32.066
O - 15.9994 * 4 = 63.998
4. Add up the results of step three:
137.327 + 32.066 + 63.998 = 233.391 g/mol (BaSO4 molecular weight)
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