Virtual Lab Worksheet
Name ______
PURPOSE:
To determine the percentage of water in a hydrate.
Computer simulation link: introchem.chem.okstate.edu/DCICLA/Empirical.html
DATA:
Initial Mass of Hydrate: _____________
Final Mass of Anhydrous Salt: _____________
CALCULATIONS:
1. Determine the mass of water in the hydrate: ____________
2. Determine the percent of water in the hydrate: ______________
3. Determine the number of moles of H20 in the hydrate: ____________
4. Determine the number of moles of the anhydrous Salt: ____________
5. Using the reaction below determine the number of water molecules per mole of
copper (II) sulfate hydrate:
CuSO4 . xH2O Determine "x", where x is a whole number.
Hint: step 1- Use the number of moles of water and copper sulfate calculated above
step 2- Divide by the smallest mole number
step 3- Round to the nearest whole number
Answer the questions below.
1. Indigo, C16H10N2O2, is the common name of the dye that gives blue jeans their
characteristic colour. Calculate the mass of oxygen in 25.0 g of indigo.
2. A mining company wishes to extract manganese metal from pyrolusite ore,
MnO2.
(a) What is the percentage composition of pyrolusite ore?
(b) Use your answer from part (a) to calculate the mass of pure manganese that can be
extracted from 250 kg of pyrolusite ore.
3. An inorganic salt is composed of 17.6% sodium, 39.7% chromium, and 42.8%
oxygen. What is the empirical formula of this salt?
4. Olive oil is used widely in cooking. Oleic acid, a component of olive oil, contains
76.54% carbon, 12.13% hydrogen and 11.33% oxygen by mass. What is the
empirical formula of oleic acid?