Tutorials and Problem Sets

Tutorials

1. Determining the Molecular Weight of a Substance from its Formula
2. The Mole and Molar Mass
3. Calculating Grams Given the Moles of a Substance
4. Calculating Moles Given Grams of a Substance
5. Avogadro Number Calculations I - Calculating the Mass of One Molecule
6. Avogadro Number Calculations II - How Many Atoms or Molecules? (10) (15)
7. Some Review Problems About Molar Mass, Moles, and Avogdro's Number
8. How to Calculate an Average Atomic Weight
9. Calculating Isotopic Abundances Given the Average Atomic Weight
10. Percent Composition
11. Empirical Formula
12. Determining Molecular Formulas from Empirical Formulas
13. Determining Empirical Formulas by Combustion Analysis (10)

Problem Sets

1. Worksheet - Molar Mass, Answers
2. 28 of the above worksheet problems in an HTML file, Handwritten solutions
3. Some Bonus Empirical Formula Problems
4. Determine empirical formula from percent composition data (10) (15)
5. Determine empirical formula from mass data (10) (10)
6. Determine identity of an element from a binary formula and a percent composition (10)
7. Determine identity of an element from a binary formula and mass data (10) (10)
8. Determine molecular formula using the Ideal Gas Law
9. Determine formula of a hydrate (10) (10) (15)
10. Hydrate lab calculations

Other Resources

Videos

1. Converting Between Moles and Mass I
2. Calculate mass of a sample with same number of atoms as a second sample
3. How to Determine Percent Abundances
4. Determine an isotopic weight from percent abundances
5. Determine an atomic weight from mass and formula data
6. Calculate an empirical formula I
7. Calculate an empirical formula II
8. Determine the molecular formula
9. Determine the water of hydration for sodium carbonate
10. Calculate an atomic weight using mass data of several compounds

Videos which use Avogadro's Number

1. Calculating a value for the Avogadro Constant
2. An illustration of the size of Avogadro's Number
3. Given 14.05 g of SO₂, how many molecules is this?
4. Given 4.91 x 10²² formula units of CuSO₄, how many grams is this?
5. What is the mass, in milligrams, of 19 atoms of nickel?
6. How many total atoms are in 27.2 g of SF₆?
7. How many oygen atoms in 4.64 x 10^-3 mol of Al(NO₃)₃?
8. How many atoms of hydrogen are in 100 g of methane?
9. Determine number of atoms using volume and density
10. Using Avogadro's Number coupled with the Ideal Gas law

Links

1. Two (of many) on-line molecular weight calculators:
   • A scientific calculator with molecular weight calculator built-in
   • A molecular weight calculator set up as a list of elements in alphabetical order

Miscellaneous

1. Some Avogadro Number Analogies
2. Origin of the word "mole"