massaprocentage

Mass percentage, also called mass percent or weight percent, is a way to express the concentration of a component in a mixture. It is defined as the mass of a component divided by the total mass of the mixture, multiplied by 100. This makes it a percentage value that reflects how much of the total mass is contributed by that component.

The mathematical relation is w_i = (m_i / m_total) × 100%, where m_i is the mass of component i and m_total is the total mass of the mixture (the sum of all components). In a solution, the mass percentage of the solute is based on the mass of the solute divided by the mass of the entire solution, which includes both solute and solvent. The corresponding mass fraction is w_i = m_i / m_total, and mass percentage is simply 100 times that fraction.

Key characteristics include that the percentages of all components in a mixture add up to 100%, and that mass percentage is based on mass rather than volume or amount of substance. It is commonly used for solids, powders, and formulations where precise mass measurements are feasible, and is useful in contexts such as chemical formulations, food and beverage analysis, and quality control. Determination typically relies on direct mass measurements or calculations from known masses; densities or temperatures can be used to assist when needed.

Example: 5 g of solute in 95 g of solvent yields a total mass of 100 g, so the mass percentage of solute is 5%.