The unit used to express weighted average atomic mass is the dalton, also known as the unified atomic mass unit. One dalton is defined as 1/12 of the mass of a carbon-12 atom, which contains six protons and six neutrons.... More »

The actual humidity in terms of the water content of air is typically expressed as grams per kilogram or kilogram per kilogram. Humidity is typically expressed as a percentage of how humid it could physically be at a giv... More »

The unit used to measure weight in the metric system is the gram. Other metric units for weight include the kilogram, the metric ton and the milligram. More »

The atomic theory formulated by the British chemist John Dalton proposes that atoms are indivisible particles comprising all matter; atoms of the same element share identical properties, including shape, size and mass; a... More »

Atomic mass is a measure of the mass of a single atom of a single isotope of an element when it is at rest, while atomic weight is a somewhat more complicated measurement that takes into account the relative abundance of... More » Science Chemistry Atoms & Molecules

The atomic mass is not given as a whole number because it is a weighted average taken of all of an atom's isotopes found in nature relative to the mass of carbon-12. The measurement unit used for atomic mass is the unifi... More »

The standard for the atomic mass unit is 1/12th of the mass of the carbon-12 atom. The units for the masses of atomic particles are typically expressed in "amu" or "u." More » Science Chemistry Atoms & Molecules