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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 an element?

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The molar mass of an element is the mass of one mole of that element, typically expressed in grams per mole (g/mol). It is numerically equivalent to the atomic mass of the element.

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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 6.022 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 number of molecules in a given mass of a substance?

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To calculate the number of molecules, first convert the mass to moles using the molar mass, then multiply the number of moles by Avogadro's number. Formula: Molecules = Moles x Avogadro's number.

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What is the mass of one mole of water (H2O)?

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The mass of one mole of water is approximately 18.02 g.

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How many moles are in 100 g of sodium chloride (NaCl)?

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To find the moles in 100 g of NaCl, divide 100 g by the molar mass of NaCl (58.44 g/mol). Moles = 100 g / 58.44 g/mol ≈ 1.71 moles.

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What is the formula to find the molar mass of a compound?

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To find the molar mass of a compound, sum the molar masses of all the atoms in its chemical formula. For example, for H2O: (2 x H) + (1 x O) = (2 x 1.01 g/mol) + (1 x 16.00 g/mol) = 18.02 g/mol.

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How do you find the number of moles from the number of formula units?

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To find the number of moles from the number of formula units, divide the number of formula units by Avogadro's number. Formula: Moles = Formula Units / Avogadro's number.