Think First

1. Get a chemistry text book and finish problems 42-57, pp. 328-337.

2. When you finish, show me your work.

3. Finish by _______

4. If you finish early, begin the pink homework handout titled “Calculating Empirical and Molecular Formulas.”

Study session after school on Thursday

•The mole test next class

•Formal lab due 4/12, 15

Hydrates

• A compound with a specific number of water molecules bound to its atoms– Example: CuSO4•5H20 Copper(ll) sulfate

pentahydrate– How can you determine the formula for a

hydrate? Read page 339 in the chemistry text.

Most Important Part: Show all your mathematical work for:

•Calculate the formula of the hydrate (Analyze and Conclude Question #1)

•Calculate Percent Error (Analyze and Conclude Question #4)

In your composition book record:

•A hypothesis

•A data table

•A bar graph showing mass or moles before and after heating

•Any differences between the procedure in the book and your procedure

•Questions 1-5 in Analyze and Conclude on page 343

•A conclusion (connect to hypothesis, error analysis, importance, future plans)

Read Lab Directions First

Do Lab and Collect Data

Finding the Formula of the Hydrate Lab

Objective: Use your knowledge of moles to find the formula of a hydrate.

The Mole Unit Exam

• Quiz on Friday/Monday over:– Calculating the number of moles, mass, or particles

given the number of moles, mass or particles• Calculating the molar mass of a compound• How to set up the problem and show all your work

– Calculate the percent composition of a compound from percentages of elements in a compound

– Calculate the molecular formula– Calculate the formula of a hydrate given the number

of grams of the hydrated compound and the number of grams of water released.