Chemistry

Antonia Ciunci

Chemistry .2a

Quarter: 3

Chapter: 10

Lab Activity: Formula for a Hydrate

DIRECTIONS: This lab activity is to be submitted as a home work hand in. Fill this out on your computer and submit it electronically. It is due, at the latest, when class meets the day after it was completed. Answer the following sections only and be sure to show all mathematical calculations. Be thorough with your answers. You will need your lab manual and lab data to complete the lab.

• Purpose (please discuss the reasons why this lab was performed and what concepts from class it targets):

This lab was performed so that we were able to learn how to determine the number of water molecules attached to each CuSO4 molecule. Also, by knowing this, we learned further how to use moles with different math operations and how to determine the number of water molecules attached to any element given certain information. This targets the study of Moles we are doing in class. A mole is a chemical mass unit of measurement that is defined to be 6.022 x 10 to the 23rd power (10^23). This is Avogadro's number and it represents the amount of a substance that contains as many atoms, molecules, ions, or other units of atoms in the given substance.

• Data from experiment:

1. Mass of crucible: 24.06 g

2. Molar mass of crucible and blue cusoy: 26.06 g

3. Mass of blue cusoy: 2.0 g

4. Mass of H2O lost: 0.56 g

            -before: 2.0 g

            -after: 1.44 g

                   (2.0-1.44)     

5. Mass of dry crystals: 1.44

            -before: 25.5

            -crucible: 24.06

                   (25.5-24.06)

6. Moles of water lost: 0.031

       0.56/molar mass of water

                     =1.00794 x 2 + 15.9994

       Molar mass of water: 18.01528

      0.56/18.01528 = 0.0310847236

                              =0.031

7. 1.44/molar mass of CuSO4= 0.0090

                    =63.546+32.065+ (15.9994 x 4)

       Molar mass of CuSO4=159.6086...