Q1 QSE Review: Mole Conversions

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What is a mole in chemistry?

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A mole is a unit of measurement used to express the amount of a substance. It is defined as the amount of substance that contains as many entities (atoms, molecules, etc.) as there are in 12 grams of carbon-12.

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What is the molar mass of a substance?

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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, divide the mass of the substance (in grams) by its molar mass (in g/mol). Formula: Moles = Mass (g) / Molar Mass (g/mol).

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How do you convert moles to grams?

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To convert moles to grams, multiply the number of moles by the molar mass of the substance. Formula: Mass (g) = Moles x 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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What is the molar mass of water (H2O)?

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The molar mass of water is approximately 18.02 g/mol, calculated as (2 x 1.01 g/mol for H) + (16.00 g/mol for O).

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How many moles are in 30 grams of sodium (Na)?

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To find the number of moles in 30 grams of sodium, divide 30 g by the molar mass of sodium (approximately 22.99 g/mol). Moles = 30 g / 22.99 g/mol ≈ 1.30 moles.

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What is the mass of 2 moles of carbon dioxide (CO2)?

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The molar mass of CO2 is approximately 44.01 g/mol. Therefore, the mass of 2 moles is 2 x 44.01 g/mol = 88.02 g.

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How many molecules are in 3 moles of glucose (C6H12O6)?

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To find the number of molecules in 3 moles of glucose, multiply 3 moles by Avogadro's number: 3 moles x 6.02 x 10^23 molecules/mole = 1.81 x 10^24 molecules.

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What is the relationship between moles and molecules?

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The relationship is defined by Avogadro's number: 1 mole of any substance contains 6.02 x 10^23 entities (atoms, molecules, etc.).