Unit 8: Chemical Quantities

If you were buying a bouquet of roses for a special occasion, you probably wouldn’t ask for 12 or 24; you’d ask for one or two dozen. Similarly, you might buy a pair of gloves, a ream of paper for your printer, or a gross of pencils. Each of this units—a pair, a dozen, a gross, or a ream—represents a specific number of items. These units make counting objects easier. It’s easier to buy and sell paper by the ream—500 sheets—than by the individual sheet.

Why is this important to us? New materials, new products, new consumer goods of all kinds come on the market regularly. But before manufacturing begins on most new products, calculations involving the mole must be done.

In this unit, you will:

1. Use the mole and molar mass to make conversions among moles, mass, and the number of representative particles.

2. Determine the percent composition of the components of compounds.

3. Calculate the empirical and molecular formulas for compounds.

4. Determine the formulas for hydrates.

ª Notes

o Power Point

o Chemical Quantities Formulas

o Empirical Formulas

o Molecular Formulas

o Hydrates

ª Homework