Multiple Choice
What is the mass in grams of 5.47 × 10^19 molecules of CCl2F2 (molar mass = 120.91 g/mol)?
2. Atoms & Elements
Calculating Molar Mass
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Calculate the mass percent composition of carbon in C2H6O.
A
60.00%
B
44.44%
C
48.38%
D
52.14%
Verified step by step guidance1
Determine the molar mass of each element in the compound C2H6O. Carbon (C) has a molar mass of approximately 12.01 g/mol, hydrogen (H) is about 1.01 g/mol, and oxygen (O) is about 16.00 g/mol.
Calculate the total molar mass of the compound C2H6O by adding the molar masses of all the atoms present: 2 moles of carbon, 6 moles of hydrogen, and 1 mole of oxygen. Use the formula: Molar mass of C2H6O = (2 × 12.01 g/mol) + (6 × 1.01 g/mol) + (1 × 16.00 g/mol).
Calculate the total mass of carbon in the compound. Since there are 2 carbon atoms, the total mass of carbon is: 2 × 12.01 g/mol.
Determine the mass percent composition of carbon by dividing the total mass of carbon by the total molar mass of the compound and then multiplying by 100 to convert it to a percentage. Use the formula: Mass percent of C = (Total mass of C / Molar mass of C2H6O) × 100.
Review the calculated mass percent composition of carbon and compare it with the given options to identify the correct answer.
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