# Lecture 16, Moles

## The Mole

1. Number of atoms/molecules

2. Mass of atoms/molecules (in amu)
1. 1 average carbon atom
2. 1 average oxygen atom
3. 1 average CO2 molecule
4. 1 average (NH4)2SO4 molecule

3. Mole as counting unit

4. Mass, Moles, and molecular mass (in grams)
1. 1 mole carbon atoms
2. 1 mole oxygen atoms
3. 1 mole CO2 molecules
4. 1 mole (NH4)2SO4 molecules

5. moles and number of atoms/molecules
1. 1 mole carbon atoms
2. 1 mole oxygen atoms
3. 1 mole CO2 molecules
4. 1 mole (NH4)2SO4 molecules

## Practice Problems

1. Beer has about 10. grams of ethanol (C2H6O), how many moles of ethanol? How many moles of carbon? How many moles of Hydrogen? How many moles of Oxygen?

2. One cup of Coffee has about 50 mg of caffeine (C8N4O2H10). How many moles of caffeine? How many moles of carbon? How many moles of nitrogen? How many moles of oxygen? How many moles of hydrogen?

3. It is possible to measure a picomole of CCl4. How many grams is this?

4. It is possible to measure an attomole of sodium. How many grams is this? How many atoms?

5. In a laboratory experiment, you are required to measure out 0.0154 mole of sodium chloride. How many grams is this?