Molar Mass & Percent Composition

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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 the atoms in a chemical formula.

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How do you calculate the percent composition of an element in a compound?

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To calculate the percent composition of an element in a compound, divide the mass of the element in one mole of the compound by the molar mass of the compound, then multiply by 100.

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What is the molar mass of calcium fluoride (CaF2)?

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The molar mass of calcium fluoride (CaF2) is approximately 78.08 g/mol (calcium: 40.08 g/mol + 2 fluorine: 2 x 19.00 g/mol).

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What is the percent by mass of fluorine in calcium fluoride (CaF2)?

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The percent by mass of fluorine in calcium fluoride is 49%.

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What is the molar mass of aluminum (Al)?

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The molar mass of aluminum is 26.98 g/mol.

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How do you find the percent composition of hydrogen in hydrochloric acid (HCl)?

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To find the percent composition of hydrogen in HCl, divide the mass of hydrogen (1.01 g/mol) by the molar mass of HCl (36.46 g/mol) and multiply by 100, resulting in approximately 2.7%.

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What is the molar mass of carbon tetrachloride (CCl4)?

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The molar mass of carbon tetrachloride (CCl4) is approximately 153.82 g/mol (carbon: 12.01 g/mol + 4 chlorine: 4 x 35.45 g/mol).

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What is the percent by mass of chlorine in carbon tetrachloride (CCl4)?

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The percent by mass of chlorine in carbon tetrachloride is 92.2%.

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What is the formula for calculating percent by mass?

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Percent by mass = (mass of the element in 1 mole of the compound / molar mass of the compound) x 100.

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What is the molar mass of magnesium phosphate (Mg3(PO4)2)?

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The molar mass of magnesium phosphate (Mg3(PO4)2) is approximately 262.86 g/mol.