Conceptual Chemistry Chapter 9 Quiz 2
Name: ________________
Part I: The Mole and Atoms (You must show your work to get any credit)
1. How many grams is 3.5 moles of silicon: ______________
2. How many moles is 2.5 x 1022 atoms of germanium: _____________
3. How many atoms is 2.3 moles of potassium: ______________
Part II: The mole and compounds (You must show your work to get any credit)
1. What is the formula for Copper II Acetate: ______________
2. What is the molar mass for Copper II Acetate: ___________
3. How many grams is in 1.2 moles of Copper II Acetate: ___________
4. How many moles in in 13.4 grams of Copper II Acetate: ___________
Part III: Balancing Chemical Equations (You must show your work to get any credit)
Part IV: The Mole in Experiments (You must show work to get any credit)
18.23
1. Record the mass of an empty, clean crucible: _________________ g
2.07
2. Add 2.00 grams of Nickel II chloride to the crucible: ______________ g
20.30
3. Add the mass of the Nickel II chloride to the mass of the crucible: _______________ g
4. Set up a ring stand, Bunsen burner with a triangle (See Figure 1). We will not use the lid this
time.
5. Heat the crucible with the Nickel II chloride for 10 minutes. Then, allow the crucible to cool.
19.36
6. Record the final mass of the crucible: _________________ g
7. Calculate the change in mass of the crucible (Take Step 3 – Step 6) : ___________________ g
8. The difference that you calculated in step 7 is the amount of water that has been boiled out of
the crystal of Nickel II chloride. Determine the number of moles of water that was boiled out of
the crystal ______________________
9. Determine the grams of Nickel II chloride there are left (without water). Take Step 6 – Step 1:
______________________ g
10. Write the formula for Nickel II chloride: _______________. Determine its molar mass:
_____________________ g
11. Determine the number of moles of Nickel II chloride for step 9: ______________
12. Determine the number of water molecules per one formula unit of Nickel II chloride by dividing
your mole value in step 8 by the mole value in step 11: _________________
13. Record your formula here for the hydrate for Nickel II chloride: ________________