Molar mass and Mole Conversions

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What is molar mass?

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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 calculate the number of moles from mass?

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Number of moles = mass (g) / molar mass (g/mol).

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What is Avogadro's number?

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Avogadro's number is 6.02 x 10^23, which is the number of atoms, molecules, or particles in one mole of a substance.

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Calculate the number of atoms in 0.0340 g of Zn. (Show your work)

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Number of moles of Zn = 0.0340 g / 65.38 g/mol = 0.000519 moles. Number of atoms = 0.000519 moles x 6.02 x 10^23 atoms/mole = 3.13 x 10^20 atoms.

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What is the molar mass of PbSO4?

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The molar mass of PbSO4 is 303.27 g/mol, calculated as follows: Pb (207.2 g/mol) + S (32.07 g/mol) + 4 x O (16.00 g/mol) = 303.27 g/mol.

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How many molecules are in 2.5 moles of NaCl? (Show your work)

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Number of molecules = 2.5 moles x 6.02 x 10^23 molecules/mole = 1.51 x 10^24 molecules.

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What is the mass of 6.02 x 10^23 molecules of CO2?

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Mass = number of moles x molar mass = 1 mole x 44.0 g/mol = 44.0 g.

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How do you convert grams to moles?

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To convert grams to moles, divide the mass of the substance by its molar mass: Moles = mass (g) / molar mass (g/mol).

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Calculate the number of moles in 1.622 grams of boron. (Show your work)

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Number of moles = 1.622 g / 10.81 g/mol = 0.1500 moles.

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What is the significance of molar mass in chemical reactions?

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Molar mass is crucial for stoichiometry, allowing chemists to convert between grams and moles to predict the amounts of reactants and products in a chemical reaction.