Description Separation of a MixtureIntroduction: This experiment separates a mixture using the physical property of solubility. You will learn decantation and filtration and will use a hotplate to evaporate a liquid.You will use the Law of Conservation of Mass to check your accuracy.Background:Mixtures are combinations of substances in which the components keep their individual characteristics, can be mixed in variable proportions and can be separated by simple physical means. Contrast this with the composition of compounds that are inseparable by physical changes. Some of a mixture’s components have physical properties like melting point, boiling point, or solubility that allow us to selectively remove one component from the mixture.Then the percentage of each component in the original mixture can be calculated. Example:A student has a mixture of NaCl(s) and I2(s) weighing 2.75 grams.She heats the mixture, which turns the solid iodine into a purple gas. The salt remains as a solid.After cooling the salt, it weighs 1.59 g.To find the mass of iodine in the original sample, the student assumes that the difference in mass of the mixture and the salt is the mass of the iodine originally present.Thus: (2.75 g mixture – 1.59 g salt) = 1.16 g iodine The percent of iodine in the mixture: (1.16 g iodine / 2.75 g mixture) x 100 = 42.2% iodine in this mixtureTo find the percent of salt in the mixture: (1.59 g salt / 2.75 g mixture) x 100 = 57.8% salt in the mixtureMaterials: Procedure: WEAR YOUR GOGGLES! Obtain a sample (approximately 2.0g) of mixture of sand and salt of unknown composition. Record the sample number in your laboratory notebook.Determine the mass of a clean and dry beaker on a balance to the nearest 0.01 g
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