Mole Concept Worksheet
1. . Calculate the molar mass of each of the following:
a. (NH4)2Cr2O7 __________ g/mol
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b. CoCl2 . 6 H2O __________ g/mol
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2. Determine the mass in grams of the following:
3.00 x 1020 N2 molecules
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2.35 moles of NaHCO3
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3. The molecular formula of acetylsalicylic acid (aspirin), one of the most
commonly used pain relievers, is C9H8O4.
Calculate the molar mass of aspirin.
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a. A typical aspirin tablet contains 325 mg of C9H8O4.
How many molecules of acetylsalicylic acid is in a tablet?
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4. Manganese metal can be prepared by a thermite reaction.
4 Al(s) + 3 MnO2(s) → 3 Mn(s) + 2 Al2O3(s)
a. What mass of manganese metal (in g) can be produced from the reaction
of 2.935 g of aluminum with an excess of manganese(IV)oxide?
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b. If, in the reaction, only 2.386 g of manganese was produced, what is the
percentage yield?
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5.Calcium nitrate and ammonium fluoride react to form calcium fluoride,
nitrogen monoxide, and water vapor.
What mass of calcium fluoride is formed after 15.0 g calcium nitrate and 17.5
g ammonium fluoride are reacted?
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