Molar Mass & Gram-Mole Conversions

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What is Molar Mass?

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The molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all atoms in a molecule.

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How do you convert grams to moles?

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To convert grams to moles, use the formula: Moles = Mass (g) / Molar Mass (g/mol).

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What is the formula to find the number of atoms in a compound?

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To find the number of atoms in a compound, multiply the number of moles of the compound by Avogadro's number (6.022 x 10^23) and then by the number of atoms of each element in the formula.

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How many moles are in 22.4 g of CO2?

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To find the moles in 22.4 g of CO2, first calculate the molar mass of CO2 (12.01 + 2*16.00 = 44.01 g/mol). Then, Moles = 22.4 g / 44.01 g/mol = 0.509 moles.

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What is Avogadro's number?

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Avogadro's number is 6.022 x 10^23, which is the number of atoms, molecules, or particles in one mole of a substance.

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How do you calculate the mass of a substance from moles?

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To calculate the mass from moles, use the formula: Mass (g) = Moles x Molar Mass (g/mol).

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What is the molar mass of H2O?

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The molar mass of H2O is 18.02 g/mol (2*1.01 for H + 16.00 for O).

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How many grams are in 0.5 moles of NaCl?

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To find the grams in 0.5 moles of NaCl, first calculate the molar mass of NaCl (22.99 + 35.45 = 58.44 g/mol). Then, Mass = 0.5 moles x 58.44 g/mol = 29.22 g.

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What is the empirical formula?

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The empirical formula is the simplest whole-number ratio of elements in a compound.

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How do you determine the molecular formula from the empirical formula?

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To determine the molecular formula, divide the molar mass of the compound by the molar mass of the empirical formula, then multiply the subscripts in the empirical formula by that number.