Chemistry Separation of two solids by use of a solvent Name DRY LAB DATA
Two solids can be easily separated if both are not soluble in the same solvent. We all know that salt is soluble in water, but that sand is not. We are going to use this property for our intended separation. Measure carefully and take care not to lose any sand or salt.
Use pre-weighed, labeled beakers for this experiment. All weighing must be done
at room temperature.
1. Record the number of your sample here: sample # DRY LAB DATA.
2. Mass an empty 100 mL labeled beaker using the balance. Record its mass in the data table. Then mass an empty 250 mL labeled beaker and record its mass in the data table.
3. Pour your sample of the sand and salt mixture into the 100 mL beaker and remass it recording the mass in the data table.
4. Add approximately 20 mL of water to the mixture in the 100 mL beaker (the amount of water is not critical). Stir the mixture while heating it on a hot plate and bring it to a boil. As soon as the mixture reaches a boil, remove it from the hot plate.
5. Decant the liquid into the 250 mL beaker pouring in the salt water liquid and retaining the wet sand. To wash out the remaining salt from the sand, add another 20 mL of water to the sand, stir, and bring it to a boil and decant again. Repeat the washing one more time. Collect all of the decanted liquid in the same 250 mL beaker. At this point you should have a 250 mL beaker with about 60 mL of salt water and a 100 mL beaker with wet sand.
6. Begin to evaporate the water from the salt water by placing it on the hot plate. Stir occasionally with a glass stirring rod being careful to avoid splattering of the salt as the water level becomes lower. Go immediately to step #7.
7. Also begin to evaporate the water from the wet sand. Drying of the solid sand must be done even more carefully to avoid splattering, so stir frequently with a different stirring rod and remove the beaker from the source of heat as soon as you see any signs of splattering. When splattering subsides, return the beaker to the hot plate and continue stirring.
8. Most likely, your beakers containing the separated sand and salt will still contain some water. Place your beakers in the drying oven so that they can be dried overnight.
9. The next day, record the mass of your two beakers and their contents and record their masses in the data table. When finished with your measurements, dispose of the sand by pouring it into the trash can. Dried salt can be washed out of the beaker.
Data Table: 1. Mass of empty 100 mL beaker = 50.00 g
2. Mass of empty 250 mL beaker = 100.00 g
3. Mass of 100 mL beaker + sand and salt mixture = 54.00 g 4. Mass of 100 mL beaker + dry sand = 51.93 g
5. Mass of 250 mL beaker + dry salt = 102.05 g
Calculations:
1. Mass of salt and sand mixture initially = ______g
2. Mass of sand recovered = ______g
3. Mass of salt recovered = ______g
4. Mass of salt + mass of sand recovered = ______g
There are 3 percentage recovery calculations:
5. % of total mixture recovered = Mass of salt +mass of sand recovered X 100
Mass of salt + sand mixture initially
= ______%
6. % of sand recovered = Mass of sand recovered X 100
Mass of sand given initially
= ______%
7. % of salt recovered = Mass of salt recovered X 100
Mass of salt given initially
= ______%
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sample #DRY LAB DATA mass of salt 2.00 g mass of sand 2.00 g (true/accepted values)
calculate % error for salt calculate % error for sand calculate overall % error
= ______% = ______% = ______%
Lab requirements a) this sheet with all calculations shown ( show all work!) b) a theory and discussion section that reports error and sources of error (on an attached piece of paper).