Defining the Mole
Name____________________ Date________ Block _____
Any atomic mass on the periodic table represents the mass of one mole of atoms. One mole of iron weighs 55.845 grams.
One mole of zinc weighs 65.39 grams. In both samples there are the same number of atoms 6.02 x 1023, but zinc atoms are
bigger and heavier (remember those protons & neutrons?) than gold atoms, so a mole of zinc weighs more.
Part I Instructions: Use a periodic table to fill in the blanks.
For atoms:
1. One mole of magnesium weighs _________ grams.
2. One mole of strontium weighs _________ grams.
3. One mole of silver weighs _________ grams.
4. One mole of argon weighs _________ grams.
For molecules:
5. One mole of potassium chloride ________________ weighs _________ grams.
6. One mole of calcium bromide ________________ weighs _________ grams.
7. One mole of sodium hydroxide ________________ weighs _________ grams.
For atoms:
8. What is the mass of one mole of carbon? ____________ grams.
9. What is the mass of one mole of cobalt? _____________ grams.
10. What is the mass of one mole of sodium? _____________ grams.
For molecules:
11. What is the mass of one mole of titanium oxide________________? _____________ grams.
12. What is the mass of one mole of lithium oxide________________? ______________ grams.
For atoms:
13. What is the mass of 6.02x1023 atoms of zirconium? _______________grams.
14. What is the mass of 6.02x1023 atoms of radon? _______________grams.
For molecules:
15. What is the mass of 6.02x1023 molecules of aluminum chloride________________? _______________grams.
16. What is the mass of 6.02x1023 atoms of tin fluoride________________? _______________grams.
Part II Unit Conversion Problems: Atoms & Molecules
Show all work for the following atom/molecule mole conversion problems by using Avogadro’s number. Remember 1 mole
= ____________________ atoms or molecules. Be sure to enter parentheses around any number in scientific notation when
you enter it into your calculator.
1. Convert 3.52 x 10 26 atoms of gold to moles of gold.
2. Convert 9.2 x 10 22 atoms of silver to moles of silver.
3. Convert 5.2 x 1021 molecules of titanium hydroxide ________________ to moles of titanium hydroxide.
4. Convert 1.56 moles of gold oxide ________________ to molecules of gold oxide. (Hint-flip your conversion factor to get
moles to cancel)
Part III Gram to mole/mole to gram conversions
Use the notes that you took during class discussion and the sample problems you did for HW as a model to solve the
following problem. Show all work for the following mass mole conversion problems.
1. Convert 0.24 moles of magnesium to grams of magnesium.
2. Convert 1.7 moles of nickel to grams of nickel.
3. Convert 0.049 moles of sodium chloride ________________ to grams of sodium chloride.
4. Convert 4.5 grams of iron III oxide ________________ to moles of iron III oxide.
5. Convert 2.00 grams of water ________________into moles of water.
6. Convert 75.57 grams of potassium bromide ________________into moles of potassium bromide.
Part IV Mixed Review Homework
Instructions: complete the following unit conversion problems and show all work. These will be graded for correctness.
1. Find the number of moles in 15 grams of silver.
2. A pure gold ring weighs 23.5 grams. How many atoms of gold are in the ring?
3. How many moles of iron II oxide are in a nail that weighs 12.4 grams?
4. A gold bullion bar used in banking and international trade has a mass of 400 ounces. One ounce equals 31.10 grams. How
many atoms of gold are in a gold bar?
5. A carat has a mass of .25 grams. A diamond is made of pure carbon. How many carbon atoms are there in a 2.9 carat
diamond?
6. The FDA recommends that we eat 1.3 grams of calcium per day. How many moles of calcium should we be eating per
day?
7. The FDA recommends that adults consume 9 x 10 -4 grams of copper per day to help with enzymes that work in your liver.
a. Calculate the number of atoms of copper you consume each day
b. Calculate the moles of copper you consume each day
8. In a laundry tablet, there are 0.750 grams of sodium carbonate. Calculate the number of molecules that are in the laundry
tablet.