WorksheetsUnit 4b: Hydrates Lab Review
Total questions: 7
Worksheet time: 15mins
A student obtained the following data to determine the percent by mass of water in a hydrate. What is the approximate percent by mass of water in the hydrated salt?
2.5%
88%
12%
98%
A hydrate of magnesium chloride is present and the following data is collected:
mass of test tube = 22.130 grams
mass of test tube + hydrate = 25.290 grams
mass of test tube and sample after heating = 23.491 grams
What is the mass of the anhydrous MgCl2?
1.799 g
3.160 g
1.361 g
23.491 g
Determine the formula of CuSO4 · XH2O given the following data:
Test Tube = 23.56 g
Test Tube + Hydrate = 26.06 g
Test Tube + Anhydrate = 25.16 g
CuSO4 · H2O
CuSO4 · 2H2O
CuSO4 · 4H2O
CuSO4 · 5H2O
Which of the following was not a safety precaution we took during the hydrate lab?
Tie long hair back
Keep water valve closed during entire experiment
Use tongs to hold the test tube over the Bunsen burner
Wear safety goggles at all times
What should you do if you cannot light the bunsen burner or if there is a problem with your bunsen burner?
wait for the room to fill with methane gas
turn off the gas nozzle
ask a friend at another station
keep trying to light it
Which of the following is the correct equation for the heating decomposition of calcium phosphate tetrahydrate?
Ca3(PO4)2 ⋅ 3H2O + heat → Ca3(PO4)2 + 3H2O
Ca3(PO4)2 ⋅ 4H2O → Ca3(PO4)2 + 4H2O + heat
Ca3(PO4)2 ⋅ 4H2O + heat → Ca3(PO4)2 + 4H2O
Ca3PO4 ⋅ 4H2O + heat → Ca3PO4 + 4H2O
How can you ensure that the lab is performed with as much accuracy as possible?
Heat the test tubes for longer
Add water to the samples
Add more of the hydrate/anhydrate/unknown
Perform multiple trials for each sample tested
