Properties of Materials PDF

2. PROPERTIES OF MATERIALS SYNOPSIS:  A solution is a homogeneous mixture composed of two or more substances. Components: Solvent: The substance in which the solute is dissolved (usually in a larger amount). Solute: The substance that is dissolved in the solv...

2. PROPERTIES OF MATERIALS SYNOPSIS:  A solution is a homogeneous mixture composed of two or more substances. Components: Solvent: The substance in which the solute is dissolved (usually in a larger amount). Solute: The substance that is dissolved in the solvent.  Properties of Solutions: Homogeneity: Solutions are uniform throughout. Transparency: Solutions are usually transparent, although they can have color. Stability: Solutions do not separate upon standing and cannot be separated by filtration.  Solubility:  The ability of a solute to dissolve in a solvent at a specific temperature and pressure. Factors Affecting Solubility: Temperature: Most solids become more soluble in liquids as temperature increases, while gases become less soluble. Pressure: Affects the solubility of gases in liquids; higher pressure increases solubility. Nature of Solute and Solvent: "Like dissolves like," meaning polar solvents dissolve polar solutes, and nonpolar solvents dissolve nonpolar solutes.  Concentration of Solutions: Dilute vs. Concentrated Solutions: Dilute Solution: Contains a small amount of solute relative to the solvent. Concentrated Solution: Contains a large amount of solute relative to the solvent.  Units of Concentration: Percent (%) Solution: Amount of solute in 100 parts of solution. Parts per Million (ppm): Amount of solute in one million parts of solution. Molarity (M): Moles of solute per liter of solution.  Preparing Solutions: Steps: Measure the solvent. Add the solute to the solvent. Stir until the solute is completely dissolved. Examples and Applications: Everyday Examples: Saltwater, sugar in tea, carbonated beverages. Scientific and Industrial Applications: Pharmaceuticals, chemical reactions, cleaning agents.  Activities and Experiments: Making a Salt Solution: Dissolving table salt in water and observing the dissolving process. Effect of Temperature on Solubility: Dissolving sugar in hot and cold water to compare solubility rates. Concentration Experiments: Creating solutions of varying concentrations and testing properties such as taste or conductivity.  Planning a investigation: A variable refers to any factor, trait, or condition that can exist in differing amounts or types. Variables are essential in scientific experiments because they allow researchers to test hypotheses and observe how changing one factor can affect another. There are several types of variables commonly used : The variable you change is called Independent variable(Temperature) The variable you measure is called Dependent variable( Number of spatula used) The variable you keep the same are Control Variable( Volume of water is kept the same)  Paper chromatography is a laboratory technique used to separate mixtures of substances into their individual components. Applications of Paper Chromatography: Identifying Substances: Determining the components of inks, dyes, and plant pigments. Purity Testing: Checking the purity of pharmaceuticals and chemicals. Food Industry: Analyzing food colors and additives. Forensic Science: Identifying substances in crime scene investigations.  Advantages of Paper Chromatography: Simple and inexpensive. Requires minimal equipment and materials. Can be performed quickly and easily.  Limitations of Paper Chromatography: Not suitable for very complex mixtures. Limited to substances that can be dissolved in a solvent and carried by the paper.  Activities and Experiments: Separating Ink Colors: Use different brands of markers to see how their colors separate. Plant Pigment Analysis: Extract pigments from leaves and separate them to study their composition. Food Coloring Separation: Test various food colorings to observe the different dyes used.