When calculating percent composition, which unit of measurement is typically used for mass?

In calculating percent composition, mass is typically measured in grams because grams provide a standardized way to express the mass of a substance. Percent composition is determined by dividing the mass of each component of a compound by the total mass of the compound and then multiplying by 100 to get the percentage. Since the gram is the standard unit of mass in chemistry, it ensures that the calculations are based on a consistent and universally accepted metric.

The other units of measurement listed, such as milliliters, moles, and liters, serve different purposes. Milliliters are a unit of volume, not mass, which makes them inappropriate for this type of calculation. Moles are a unit that measures the amount of substance based on the number of particles, not mass directly. Liters are also a unit of volume, used for measuring liquids. Therefore, using grams aligns with the requirements of percent composition calculations, as it directly relates to mass and allows for accurate determination of the composition of a compound.