Understanding Mass Percent Composition and Conversion Factors

What is the primary nutrient of interest in calcium nitrate for plants?

• Calcium

• Nitrogen

• Hydrogen

• Oxygen

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

• Add the mass of the element to the total mass of the compound

• Divide the mass of the element by the total mass of the compound and multiply by 100%

• Multiply the mass of the element by the total mass of the compound

• Subtract the mass of the element from the total mass of the compound

In the example of CO2, what is the mass percent composition of oxygen?

• 50%

• 72.70%

• 27.30%

• 100%

What can mass percent composition be used for?

• To determine the color of a compound

• To convert between the mass of a compound and the mass of an element within it

• To calculate the volume of a compound

• To find the density of a compound

If zinc sulfate is 40.1% zinc by mass, how much zinc sulfate is needed to provide 11 mg of zinc?

• 40 mg

• 100 mg

• 11 mg

• 27 mg

What is the inherent conversion factor in the chemical formula ZnSO4?

• 1 mole of ZnSO4 to 2 moles of oxygen

• 1 mole of ZnSO4 to 4 moles of oxygen

• 1 mole of ZnSO4 to 3 moles of oxygen

• 1 mole of ZnSO4 to 1 mole of oxygen

How many moles of oxygen are in 6.2 moles of zinc sulfate?

• 6.2 moles

• 24.8 moles

• 25 moles

• 12.4 moles

What is the first step in converting the mass of a compound to the mass of an element without using mass percent composition?

• Use the density of the compound

• Directly calculate the mass percent composition

• Convert the mass of the compound to moles using its molar mass

• Convert the mass of the element to moles

What is the final mass of oxygen in 9.421 grams of zinc sulfate?

• 1.867 grams

• 7.468 grams

• 9.421 grams

• 3.734 grams

What is the benefit of using chemical formulas as conversion factors?

• It allows for the conversion between the amount of a compound and the amount of an element

• It provides the color of the compound

• It gives the density of the compound

• It determines the boiling point of the compound