The vapour density of Hg vapour is 6.92 with respect to air so its mol...
At the same temperature and pressure, equal moles of all gases have the same volume. So 1 mole of air and 1 mole of mercury vapour occupy the same value. Therefore saying that mercury vapour is 6.92 times denser than air also means that 1 mole of mercury vapour weighs 6.92 times 1 mole of air. Since 1 mole of air weighs 29g, 1 mole of mercury vapour weighs 6.92 x 29 = 200.68g The atomic mass of mercury is 200g. So approximately 200/200 = 1 atom is present in each mercury molecule.
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The vapour density of Hg vapour is 6.92 with respect to air so its mol...
Explanation of the Vapour Density of Hg Vapour
Vapour density is defined as the ratio of the mass of a certain volume of a gas to the mass of an equal volume of hydrogen gas at the same temperature and pressure. In the case of mercury (Hg) vapour, its vapour density is 6.92 with respect to air.
Calculating the Molecular Mass of Hg
To determine the molecular mass of mercury, we need to first calculate the molar mass of the gas. Given that the vapour density of Hg vapour is 6.92, we know that the molar mass of mercury vapour is 6.92 times that of hydrogen gas (H2), which has a molar mass of approximately 2 g/mol.
Therefore, the molar mass of mercury vapour is 6.92 x 2 = 13.84 g/mol.
Converting Molar Mass to Molecular Mass
The molecular mass of a substance is the sum of the atomic masses of all the atoms in a molecule. The atomic mass of mercury (Hg) is approximately 200.59 g/mol.
Since the molar mass of mercury vapour is 13.84 g/mol, we can calculate the molecular mass of mercury vapour by multiplying the molar mass by the atomic mass of mercury:
Molecular mass = Molar mass x Atomic mass
Molecular mass = 13.84 g/mol x 200.59 g/mol
Molecular mass ≈ 200.68 g/mol
Therefore, the molecular mass of mercury vapour is approximately 200.68 g/mol.
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