Percent Composition Calculations
Chemistry ⇒ Stoichiometry and Chemical Calculations
Percent Composition Calculations starts at 9 and continues till grade 12.
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See sample questions for grade 11
A 10.0 g sample of a compound contains 2.0 g of hydrogen. What is the percent by mass of hydrogen in the compound?
A 25.0 g sample of a compound contains 10.0 g of oxygen. What is the percent by mass of oxygen in the compound?
A compound contains 24.3% magnesium, 27.0% phosphorus, and 48.7% oxygen by mass. What is the empirical formula of the compound?
A compound has a molar mass of 180 g/mol and contains 72 g of carbon per mole. What is the percent composition of carbon?
A 10.0 g sample of a compound contains 2.0 g of hydrogen. What is the percent by mass of hydrogen in the compound?
A 25.0 g sample of a compound contains 10.0 g of oxygen. What is the percent by mass of oxygen in the compound?
A compound contains 24.3% magnesium, 27.0% phosphorus, and 48.7% oxygen by mass. What is the empirical formula of the compound?
A compound has a molar mass of 180 g/mol and contains 72 g of carbon per mole. What is the percent composition of carbon?
Which element has the highest percent composition in C6H12O6? (1) Carbon (2) Hydrogen (3) Oxygen
Which of the following best describes percent composition? (1) The ratio of atoms in a compound (2) The mass percentage of each element in a compound (3) The number of moles of each element in a compound (4) The volume percentage of each element in a compound
Which of the following compounds has the highest percent by mass of oxygen? (1) H2O (2) CO2 (3) Na2O (4) SO2
Which of the following compounds has the lowest percent by mass of hydrogen? (1) H2O (2) NH3 (3) CH4 (4) C2H6
Fill in the blank: The percent composition of chlorine in KCl is __________.
Fill in the blank: The percent composition of magnesium in MgSO4 is __________.
Fill in the blank: The percent composition of oxygen in H2O is __________.
Fill in the blank: The percent composition of phosphorus in P2O5 is __________.
A compound contains 40% sulfur and 60% oxygen by mass. Is this percent composition possible for SO2?
True or False: Percent composition can be used to identify an unknown compound.
True or False: The percent composition of a compound can be used to determine its empirical formula.
True or False: The percent composition of a compound depends on the sample size.
