Separating Sand and SaltPurpose:The purpose of this experiment is to study the physical properties of salt and sand and to carry out a procedure to separate a mixture of these substances. The percent recovery of the salt in the mixture and the percent error will be calculated from the mass of the recovered components.Background:A mixture is a combination of two or more pure substances that retain their separate chemical identities and properties. Since the amounts of each substance making up a mixture can be changed, the physical properties of a mixture depend on its composition. In contrast, the composition of a pure substance is constant, and thus pure substances have characteristic physical properties that do not change. Examples of physical properties that can be used to describe pure substances include solubility, conductivity, magnetism, density, boiling point, and melting point.By taking advantage of the unique physical properties of individual components within a mixture, it should be possible to separate a mixture into its components. For example, if one component in a mixture of two solids dissolves in water, while a second component does not, the components can be separated by adding water to the mixture and then decanting the solution into a separate container.???????????=?????????????????????????????????×100???????????????=???????????????????????????????????????????????×100Percent Error=experimental mass―true mass????????×100Materials Salt. Most households have table salt in the kitchen. If you’re in a pinch, you can get salt packets from a fast food restaurant. Sand. Although it depends on where you live, sand should be very easy to find. A pan and heating element. A second pan  Disposable cups DI Water from the storeNotes for SubmissionIf you have access to a printer, please print out any sheets on which you write down numbers, calculations, and answers to questions. If you do not have a printer, be prepared to neatly write your data, analysis, and responses to all questions on sheets of paper. Most likely, you will be asked to take photos

of your written pages, turn them into a single pdf file, and upload them in Canvas for your instructor to grade. Be sure to follow any specific directions given to you by your instructor.ProcedureExact measurements are not needed, but multiple trials will help you assess precision. Several steps in this procedure require you to use an electronic kitchen scale. If you were not able to get a scale, your instructor might ask you to work in a group with a student who does have a kitchen scale. Or, your instructor might ask you to perform the experiment without collecting masses (and they might give you sample data to work with). Please consult with your instructor regarding expectations for this lab. Before you begin this procedure, it is recommended that you read all steps carefully and then draw a flowchart of what you will be doing. In your flowchart, draw pictures of the pans that you will use, as well as indications of when water is added, when components are separated, etc. 1. You should have between 15 g and 16 g of salt and sand each. This roughly equates to 1 tablespoon of each. a. If the sand has a lot of chunks it, you should sift those out first using a strainer. b. Weigh the mass of salt and sand separately in a tared disposable cup on the electronic scale. c. In the data table, record your observations of how the salt and sand look.2. Salt and sand mix together very well, and you can mix them together by shaking the pan around. If that doesn’t work, stir it around until the two are thoroughly mixed.a. Take mass of this first empty pan on the electronic balance. b. Take mass of the first pan with dry salt/ sand mixturec. Record the appearance of the mixture in the data table. 3. Add DI water to the sand and salt. a. Add just enough water to cover the salt and sand. b. Too much water will make the experiment take too long, as you will then have a lot of water that you will need to boil off later.c. Take a picture of your work so far. This is image SS014. Heat the mixture. Heat is the active ingredient when it comes to stirring up particles. A bit of heat will cause the salt to dissolve in the water. a. Use low to medium heat on a stovetop for about 3 minutes.b. Make sure not to heat the water to the point of boiling! This will simply cause the water to evaporate, and we want to avoid evaporation at this point. 5. Take the mass of a second, empty pan. Then decant (pour off) the water solution (water with salt dissolved) into a second pan.6. Repeat steps 3 and 4. (Go back to the original salt and sand mixture in the first pan, add more DI water, heat, and decant into the same second pan that you decanted into above.)a. This is to make sure all the salt was pulled out of the original mixture.7. Boil the saltwater in the second pan. a. You need to return the salt to its original state. This can be done by boiling the water. Put the (second) pan on a stovetop and let the water boil. Wait until the water has boiled away completely. Turn off the heat. From there, you should be able to see the salt remaining in your pan.b. The boiling temperature of salt is much higher than water. So, the water will boil off, but the salt will remain in the pan. For the sake of protecting your pot, you should keep the

temperature relatively low on the stovetop. It may take longer to boil, but speed isn’t worth the risk of damage.c. Once the salt looks dry and has cooled to room temperature, get the mass of the second pan with salt.d. Take a picture of your work so far. This is image SS028. Cook the sand in the first pan until it looks dry.a. Once the sand looks dry and has come down to room temperature, get the mass of the first pan with sand. b. Take a picture of your work so far. This is image SS039. Reheat the salt and sand in their respective pans for 5 minutes.a. Reweigh both pans with salt and sand when they have cooled to room temperature.b. Describe how the separated salt and sand look. Record your observations in the data table.10. Let both pans sit 24 hours with the separated salt and sand, and then take the mass of each.a. At this point all the water should be removed and the separated materials should be at constant mass.b. Describe how the separated salt and sand look. Record your observations in the data table.c. Take a picture of your work so far. This is image SS04Space for Flowchart of Procedure:

Sample Data and Calculations:True mass Percent of salt in mixture % = true mass of salt/ (true mass of salt and sand) x 10015 g/ 30. g x 100 = 50. %Mass of salt and sand mixture (g) = Mass of first pan with mixture (g) – Mass of first empty pan (g)174 g -145 g = 29 gMass of Salt recovered (g) = Mass of pan with salt after 24 hours (g) – Mass of first empty pan (g)181 g -168 g = 13 gMass of Sand recovered (g) = Mass of pan with sand after 24 hours (g) – Mass of first empty pan (g)160 g – 145 g = 15 g% salt recovered in separation (%) = Mass of Salt recovered (g) / True mass of salt (g) x 100(13 g / 15 g) x 100 = 87% % salt error = (Mass of Salt recovered – True mass of salt) / True mass of salt x 100(13 g – 15 g)/ 15 g x 100% = -10%True mass of salt (g) and appearance15 g crystalline, white, specs True mass of sand (g) and appearance15 g grainy, kind of clumpy, brown specsTrue mass Percent of salt in mixture %50. %Mass of first empty pan (g)145 gMass of first pan with salt / sand mixture (g)174 gMass of salt / sand mixture (g) and appearance29 g fairly uniform mix, brown and white specsTake mass of second empty pan (g)168 gTake mass of pan with salt first heating (g)184 gTake mass of pan with sand first heating (g)160 gMass and appearance of pan with salt second heating (g)182 g white, clumpy, wetMass and appearance of pan with sand second heating (g)160 g tan, clumpy, some white specsMass and appearance of pan with salt after 24 hours (g)181 g white, flaky, some brown specs present, clumpy; much drier than yesterdayMass and appearance of pan with sand after 24 hours (g)160 g lighter brown color than original sand, clumpy; much drier than yesterdayDetermine Mass of Salt recovered (g)13 gDetermine Mass of Sand recovered (g)15 gDetermine % salt recovered in separation (%)87%Determine % salt error-10%

Data and Calculations:True mass of salt (g)True mass of sand (g)True mass Percent of salt in mixture %Mass of first empty pan (g)Mass of first pan with salt / sand mixture (g)Observation of salt / sand mixtureMass of salt / sand mixture (g)Take mass of second empty pan (g)Take mass of pan with salt first heating (g)Take mass of pan with sand first heating (g)Mass and appearance of pan with salt second heating (g)Mass and appearance of pan with sand second heating (g)Observation of dry saltObservation of dry sandMass and appearance of pan with salt after 24 hours (g)Mass and appearance of pan with sand after 24 hours (g)Determine Mass of Salt recovered (g)Determine Mass of Sand recovered (g)Determine % salt recovered in separation (%)Determine % errorCalculations: