Empty all of your sample into the beaker and determine the mass of the beaker and the sample.Measure 25-mL of distilled water in the graduated cylinder and add the water to the beaker with the mixture. Stir thoroughly with the stirring rod to dissolve the salt. You may want to gently heat this mixture. While salt is very soluble in water, it can take some time for complete dissolution. Heating will speed this up. Determine the combined mass of a watch glass and a piece of filter paper. Record this mass. Fold the filter paper, as shown in figure below, and fit into the funnel.Place the filter funnel on top of the Erlenmeyer flask. Moisten the filter paper with distilled water from the bottle and press it to the walls of the funnel, so that it adheres.Filter the mixture by decanting the liquid slowly into the center of the funnel. The liquid filtered through will be collected in the Erlenmeyer flask.Note: Pour the liquid through the funnel at such a rate as not to overfill the funnel.After all the liquid has been filtered, use two 5 mL portions of water to transfer any sand remaining in the beaker to the filter paper.10. Use three additional 5 mL portions of water to wash the material on the filter paper. (The first of these is also used to rinse the rubber end of the stirring rod that was used in transferring the sample).After all the water has dripped from the end of the funnel, carefully remove the filter paper from the funnel (without tearing it) and place on the watch glass and place it in the drying oven to dry.When the sample is dry, determine the mass of the watch glass, filter paper and sand, and record in your notebook.Rinse the beaker clean, but not dry, and pour the liquid from the Erlenmeyer flask into it.Place the beaker on a hot plate and heat carefully to evaporate the water off.GOGGLES ARE MANDATORY – HOT SALT SPLATTERSNote: Take caution not to overheat the beaker and splatter the salt. To avoid loss ofsample due to spattering, when the water level becomes low, heat at a gentler rateuntil you hear popping sounds. At this time remove the beaker from the hot platecarefully, and return when the popping action has stopped.Remember to turn off the hot plate when done.When all the water has been evaporated, remove the beaker from the hot plate carefully, and let cool on the bench. Do NOT place the hot beaker directly on the benchtops. Instead place the beaker on top of a wire gauze. After the beaker has cooled to the touch, determine its mass with the salt, and record this value in your notebook. Place the beaker on the hot plate again, and carefully heat a few more minutes, watching closely for signs of excessive spattering.After the second heating, remove the beaker, cool, and determine its mass again. Record in your notebook.Compare the first and second mass obtained for the beaker and the salt.
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