Name ___________________________________ Date ______________________ Class ______________________
Chapter 10 – Chemical Quantities
Mass and Avogadro’s Number
Now that you know two definitions of a mole (a gram formula weight and an Avogadro’s number of particles) you can
combine these two definitions into one problem.
Example: How many molecules are there in 90.1 grams of water?
Example: What would be the mass of 3.01x1023 molecules of ammonia (NH3)?
Solve the following problems. You must show your work and include units.
1. How many molecules are there in 345 grams of carbon dioxide?
Calculation:
Formula: _______________
Answer: _______________
2. What would be the mass, in grams, of 1.204x1024 molecules of sulfur dioxide?
Calculation:
Formula: _______________
Answer: _______________
3. How many molecules of sucrose, C6H12O6, are there in 454 grams of sucrose?
Calculation:
Formula: _______________
Answer: _______________
4. What would be the mass, in grams, of 1.806x1024 molecules of carbon monoxide?
Calculation:
Formula: _______________
Answer: _______________
5. How many molecules of water are there in 8.050x103 grams of water?
Calculation:
Formula: _______________
Answer: _______________
6. How many oxygen molecules are in a flask that contains 1.43 grams of oxygen?
Calculation:
Formula: _______________
Answer: _______________
7. What would be the mass, in grams, of 1.505x1023 molecules of carbon disulfide?
Calculation:
Formula: _______________
Answer: _______________
8. How many molecules of hydrogen chloride would there be in 100.0 grams of this gas?
Calculation:
Formula: _______________
Answer: _______________
9. What would be the mass, in grams, of 2.408x1024 molecules of tetraphosphorus decoxide?
Calculation:
Formula: _______________
Answer: _______________
10. What would the mass of 5.89x1030 molecules of sulfuric acid, in grams?
Calculation:
Formula: _______________
Answer: _______________