Mixtures and Solutions Review Sheet

Test: June 3, 2008   Name ________________________________ Date ______________   Investigations Review   FOSS Investigation Synopsis Science Content FOSS Science Stories Separating Mixtures   Students make mixtures of water and solid materials (salt, gravel, and diatomaceous earth) and separate the mixtures with screens and filters. They find that water and salt make a special kind of mixture, a solution that cannot be separated with a filter but only through evaporation.   • A mixture combines two or more materials that retain their own properties. • A solution forms when a material dissolves in a liquid (solvent) and cannot be retrieved with a filter. • Evaporation can separate a liquid from a solid in a solution. • The solid material separated by evaporation from a solution forms distinctive patterns. • Mixtures and Solutions • A Salty Story           Reaching Saturation   Students make a saturated solution by adding salt to water until no more salt will dissolve. They also make a saturated citric acid solution. Using a balance, they compare the solubility of the two solid materials by comparing the mass of the salt and citric acid dissolved in the saturated solutions. They use the property of solubility to identify an unknown material.   • Solubility is the property that substances have of dissolving in solvents. Solubility is different for different materials and can change with temperature and different solvents. • A solution is saturated when as much solid material as possible has dissolved in the liquid. • When equal volumes of two solutions made from the same ingredients are compared, the heavier one is the more concentrated solution.   • Decompression Sickness • Sour Power           FOSS Investigation Synopsis Science Content FOSS Science Stories Concentration   Students observe and compare soft-drink solutions that differ in the amount of powder (water held constant) and that differ in the amount of water (powder held constant) to develop the concept of concentration. They make salt solutions of different concentrations and compare them, using a balance. They determine the relative concentrations of three mystery solutions made from the same solid material.   • Concentration expresses a relationship between the amount of dissolved material and the volume of solvent. • The more material dissolved in a liquid, the more concentrated the solution. • A concentrated solution can be made more dilute by adding solvent to the solution.   • Grow Your Own Crystals • The Air You Breathe           Fizz Quiz   Students systematically mix combinations of solid materials (calcium chloride, baking soda, and citric acid) with water and observe changes that occur. The changes (formation of a gas and a white precipitate) are identified as chemical reactions. Students investigate these reactions and the materials that are produced.   • When a change results from mixing two or more materials, that change is a chemical reaction. A reaction results in new materials. • Formation of a gas is one change that occurs in some reactions. • Formation of a precipitate occurs in some chemical reactions. • Not all chemicals react when they are mixed.   • What a Reaction! • What Is Matter Made Of? • Ask a Chemist • The Periodic Table • The History of Rubber      Word Bank   Atom- the smallest particle of an element   Chemistry- the branch of science that deals with the composition, structure, and properties of matter   Chemical reaction- the process in which two or more substances combine to make one or more new substances that have different properties than the original ones   Citric acid- a white, odorless acid with a sour taste   Compound- a substance made of two or more elements that are chemically combined   Concentration- the relative amount of a substance in a mixture   Crystal- the solid form of a material that can be identified by its natural shape or pattern   Dilute- a watering down of a solvent   Dissolving- the process of a material becoming incorporated uniformly into another or mixing together evenly   Element- a substance that cannot be broken down by simple chemical and physical processes   Evaporate- to turn into a gas, like water into water vapor   Mixture- a substance containing two or more materials with different properties   Periodic Table of Elements- an arrangement of the elements that provides information about their properties   Precipitate- a solid material that forms during a chemical reaction   Reactant- a chemical that takes part in a chemical reaction   Saturated solution- a solution in which as much solute as possible has been dissolved   Soluble- capable of being dissolved (table salt is soluble in water)   Solute- a substance that dissolves in a solvent to form a solution   Solution- a special mixture for when one or more materials dissolves in another   Solvent- a substance that dissolves a solute to form a solution     Concepts/Lessons to Review   FOSS Investigations Lessons/Labs/Notebook FOSS Science Stories Periodic Table of Elements (1-30) History of the Periodic Table of Elements