The mole

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What is the mole?

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The mole is a unit of measurement used in chemistry to express amounts of a chemical 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 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 molar mass of NaCl?

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To calculate the molar mass of NaCl, add the atomic mass of sodium (Na, 22.990 g/mol) and chlorine (Cl, 35.453 g/mol). Molar mass of NaCl = 22.990 + 35.453 = 58.443 g/mol.

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What is the significance of Avogadro's number?

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Avogadro's number (6.022 x 10^23) is the number of atoms, molecules, or particles in one mole of a substance. It allows chemists to convert between moles and number of particles.

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What volume does one mole of gas occupy at STP?

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At standard temperature and pressure (STP), one mole of an ideal gas occupies 22.4 liters.

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How do you find the number of moles from grams?

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To find the number of moles from grams, use the formula: Moles = Mass (g) / Molar Mass (g/mol).

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What is the molar mass of H2O?

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The molar mass of water (H2O) is calculated by adding the molar masses of 2 hydrogen atoms (2 x 1.008 g/mol) and 1 oxygen atom (16.00 g/mol). Molar mass of H2O = 2.016 + 16.00 = 18.016 g/mol.

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How do you convert moles to volume for gases at STP?

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To convert moles to volume for gases at STP, use the formula: Volume (L) = Moles x 22.4 L/mol.

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What is the relationship between moles and molecules?

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One mole of any substance contains Avogadro's number (6.022 x 10^23) of molecules or atoms.

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What is the molar mass of CO2?

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The molar mass of carbon dioxide (CO2) is calculated by adding the molar mass of carbon (12.01 g/mol) and 2 oxygen atoms (2 x 16.00 g/mol). Molar mass of CO2 = 12.01 + 32.00 = 44.01 g/mol.