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Manganese(II) chloride is the dichloride salt of manganese, MnCl 2.This inorganic chemical exists in the anhydrous form, as well as the dihydrate (MnCl 2 ·2H 2 O) and tetrahydrate (MnCl 2 ·4H 2 O), with the tetrahydrate being the most common form.
The ideal gas law can be re-arranged to obtain a relation between the density and the molar mass of an ideal gas: = and = and thus: = where: P = absolute gas pressure; V = gas volume; n = amount (measured in moles) R = universal ideal gas law constant; T = absolute gas temperature; ρ = gas density at T and P; m = mass of gas
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.
How much gas is present could be specified by giving the mass instead of the chemical amount of gas. Therefore, an alternative form of the ideal gas law may be useful. The chemical amount, n (in moles), is equal to total mass of the gas (m) (in kilograms) divided by the molar mass, M (in kilograms per mole): =.
The laws describing the behaviour of gases under fixed pressure, volume, amount of gas, and absolute temperature conditions are called gas laws.The basic gas laws were discovered by the end of the 18th century when scientists found out that relationships between pressure, volume and temperature of a sample of gas could be obtained which would hold to approximation for all gases.
M 2 is the molar mass of gas 2. Graham's law states that the rate of diffusion or of effusion of a gas is inversely proportional to the square root of its molecular weight. Thus, if the molecular weight of one gas is four times that of another, it would diffuse through a porous plug or escape through a small pinhole in a vessel at half the rate ...
What's even more admirable was her work in science, a field in which women faced many obstacles, as well as the time she spent getting her Ph.D. in chemistry from MIT– well, almost. “If MIT had allowed women to get a Ph.D. in chemistry, she would have gotten one,” said Elizabeth Maurer, director of program at the National Women's History ...
The molar mass of a substance depends not only on its molecular formula, but also on the distribution of isotopes of each chemical element present in it. For example, the molar mass of calcium-40 is 39.962 590 98 (22) g/mol, whereas the molar mass of calcium-42 is 41.958 618 01 (27) g/mol, and of calcium with the normal isotopic mix is 40.078(4 ...