Search results
Results from the WOW.Com Content Network
Oxygen is the most abundant chemical element by mass in the Earth's biosphere, air, sea and land. Oxygen is the third most abundant chemical element in the universe, after hydrogen and helium. [67] About 0.9% of the Sun's mass is oxygen. [18]
Molar mass: 216.591 g·mol −1 Appearance Yellow or red solid Odor: odorless ... Joseph Priestley discovered that oxygen was released by heating mercuric oxide, ...
Oxygen-15 is a radioisotope, often used in positron emission tomography (PET). It can be used in, among other things, water for PET myocardial perfusion imaging and for brain imaging. [20] [21] It has an atomic mass of 15.003 0656 (5), and a half-life of 122.266(43) s. It is produced through deuteron bombardment of nitrogen-14 using a cyclotron ...
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 × 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.
The atomic mass (ma or m) is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI unit dalton (symbol: Da) – equivalently, unified atomic mass unit (u). 1 Da is defined as 1⁄12 of the mass of a free carbon-12 atom at rest in its ground state. [1]
The equivalent weight of an element is the mass which combines with or displaces 1.008 gram of hydrogen or 8.0 grams of oxygen or 35.5 grams of chlorine. The equivalent weight of an element is the mass of a mole of the element divided by the element's usual valence. That is, in grams, the atomic weight of the element divided by the usual ...
Specific volume. In thermodynamics, the specific volume of a substance (symbol: ν, nu) is the quotient of the substance's volume (V) to its mass (m): It is a mass-specific intrinsic property of the substance. It is the reciprocal of density ρ (rho) and it is also related to the molar volume and molar mass: The standard unit of specific volume ...
Molar volume. In chemistry and related fields, the molar volume, symbol Vm, [1] or of a substance is the ratio of the volume (V) occupied by a substance to the amount of substance (n), usually at a given temperature and pressure. It is also equal to the molar mass (M) divided by the mass density (ρ): The molar volume has the SI unit of cubic ...