Mixing ratio
Encyclopedia
In chemistry
and physics
, the dimensionless mixing ratio is defined as the abundance of one component of a mixture relative to that of all other components. The term can refer either to mole ratio or mass ratio.
, mixing ratio usually refers to the mole ratio
, which is defined as the amount
of a constituent
divided by the total amount of all other constituents in a mixture:
The mole ratio is also called amount ratio.
If
is much smaller than 
(which is the case for atmospheric trace constituents), the mole ratio is almost identical to the mole fraction.
, mixing ratio usually refers to the mass ratio
, which is defined as the mass of a constituent 
divided by the total mass of all other constituents in a mixture:
The mass ratio of water vapor in air can be used to describe humidity.
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
and physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
, the dimensionless mixing ratio is defined as the abundance of one component of a mixture relative to that of all other components. The term can refer either to mole ratio or mass ratio.
Mole ratio
In atmospheric chemistryAtmospheric chemistry
Atmospheric chemistry is a branch of atmospheric science in which the chemistry of the Earth's atmosphere and that of other planets is studied. It is a multidisciplinary field of research and draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and...
, mixing ratio usually refers to the mole ratio
, which is defined as the amountAmount of substance
Amount of substance is a standards-defined quantity that measures the size of an ensemble of elementary entities, such as atoms, molecules, electrons, and other particles. It is sometimes referred to as chemical amount. The International System of Units defines the amount of substance to be...
of a constituent
divided by the total amount of all other constituents in a mixture:The mole ratio is also called amount ratio.
If
is much smaller than (which is the case for atmospheric trace constituents), the mole ratio is almost identical to the mole fraction.Mass ratio
In meteorologyMeteorology
Meteorology is the interdisciplinary scientific study of the atmosphere. Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the 18th century. The 19th century saw breakthroughs occur after observing networks developed across several countries...
, mixing ratio usually refers to the mass ratio
, which is defined as the mass of a constituent divided by the total mass of all other constituents in a mixture:The mass ratio of water vapor in air can be used to describe humidity.