massfraksjon

Massfraksjon, also known as mass percentage or weight percentage, is a way of expressing the composition of a mixture or solution. It is defined as the mass of a component divided by the total mass of the mixture, expressed as a percentage. The formula for massfraksjon of component A is: massfraksjon A = (mass of A / total mass of mixture) * 100%.

For example, if you have a salt solution made by dissolving 10 grams of salt in 90 grams of water, the total mass of the mixture is 100 grams. The massfraksjon of salt would be (10 g / 100 g) * 100% = 10%. The massfraksjon of water would be (90 g / 100 g) * 100% = 90%. The sum of the massfractions of all components in a mixture will always equal 100%.

Massfraksjon is a unitless quantity, though it is often expressed with the unit "%". It is commonly used in chemistry, physics, and materials science to describe the concentration of substances in a sample. Unlike molarity or molality, massfraksjon is independent of temperature and pressure, making it a convenient measure for many applications. It is particularly useful when dealing with solid mixtures or when the molar masses of the components are not known or are difficult to determine.