Search results
Results from the WOW.Com Content Network
Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...
Water vapor and dry air density calculations at 0 °C: The molar mass of water is 18.02 g/mol, as calculated from the sum of the atomic masses of its constituent atoms. The average molar mass of air (approx. 78% nitrogen, N 2; 21% oxygen, O 2; 1% other gases) is 28.57 g/mol at standard temperature and pressure .
It is a dimensionless quantity with dimension of / and dimensionless unit of moles per mole (mol/mol or mol ⋅ mol-1) or simply 1; metric prefixes may also be used (e.g., nmol/mol for 10-9). [5] When expressed in percent , it is known as the mole percent or molar percentage (unit symbol %, sometimes "mol%", equivalent to cmol/mol for 10 -2 ).
The percentage by volume (vol%, % v/v) is one way of expressing the composition of a mixture with a dimensionless quantity; mass fraction (percentage by weight, wt%) and mole fraction (percentage by moles, mol%) are others. At room temperature, water-ethanol mixture loses volume at any mixing ratio. In the case of a mixture of ethanol and water ...
The definition of a w is where p is the partial water vapor pressure in equilibrium with the solution, and p* is the (partial) vapor pressure of pure water at the same temperature. An alternate definition can be a w ≡ l w x w {\displaystyle a_{w}\equiv l_{w}x_{w}} where l w is the activity coefficient of water and x w is the mole fraction of ...
The molar mass of atoms of an element is given by the relative atomic mass of the element multiplied by the molar mass constant, M u ≈ 1.000 000 × 10 −3 kg/mol ≈ 1 g/mol. For normal samples from Earth with typical isotope composition, the atomic weight can be approximated by the standard atomic weight [ 2 ] or the conventional atomic weight.
= fraction of the emitted exhaust gas, by volume, which is water vapor Thus, a wet basis concentration of 40 ppmv in a gas having 10 volume percent water vapor would have a dry basis concentration = 40 ÷ ( 1 - 0.10 ) = 44.44 ppmv.
To convert from / to / ... Water: 5.536 0.03049 Xenon: 4.250 0.05105 Units ... 1 dm 3 /mol = 1 L/mol = 1 m 3 /kmol = 0.001 m 3 /mol ...