Do Now - AP - % Comp of a Substance

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What is the empirical formula?

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The empirical formula is the simplest whole-number ratio of moles of elements in a compound.

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How do you determine the empirical formula from combustion data?

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1. Convert the mass of CO2 and H2O produced to moles. 2. Use the moles of carbon and hydrogen to find the ratio. 3. Determine the moles of oxygen from the mass of the compound. 4. Simplify the ratio to get the empirical formula.

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What is the empirical formula of a compound that contains 0.2500 g of a sample producing 0.3664 g of CO2 and 0.1500 g of H2O?

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CH2O

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If a compound has an empirical formula of CCl2 and a molecular mass of 160 g/mole, what is its molecular formula?

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C2Cl4

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What is the relationship between empirical and molecular formulas?

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The empirical formula represents the simplest ratio of elements, while the molecular formula shows the actual number of atoms in a molecule.

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How do you find the molecular formula from the empirical formula?

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1. Calculate the molar mass of the empirical formula. 2. Divide the molecular mass by the empirical formula mass. 3. Multiply the subscripts in the empirical formula by this ratio.

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Which pair has the same empirical formula: NaCrO4 and Na2Cr2O7 or C2H4O2 and C6H12O6?

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C2H4O2 and C6H12O6 have the same empirical formula.

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What is the empirical formula of a compound containing 2.70 g of C and 15.95 g of Cl?

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CCl2

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What is the significance of the empirical formula in chemistry?

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The empirical formula helps in understanding the composition of a compound and is essential for stoichiometric calculations.

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How do you convert grams of a substance to moles?

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Use the formula: Moles = Mass (g) / Molar Mass (g/mol).