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This lecture explores the three states of matter—solid, liquid, and gas—providing examples for each. It discusses mixtures, which are physical blends of substances, and differentiates between homogeneous and heterogeneous mixtures. You'll learn about solutions, the nature of solutes and solvents, and factors affecting solubility, including temperature and pressure. Additionally, the lecture covers methods for separating mixtures like filtration and distillation, deepening your understanding of chemical compounds and mixtures in our surroundings.
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Bell Work • How can you tell the difference between the three states of matter? • Give an example of each state that is present in this room.
Physical Science – Lecture 56 Mixtures and Chemical Reactions
Chemical Compounds • The combination of two or more elements that forms one substance.
Mixtures • a physical blend of two or more substances that are not chemically combined. • If the composition of a material may vary, then the material is a mixture.
Types of Mixtures • Based on the distribution of their components, mixtures can be classified as heterogeneous mixtures or homogeneous mixtures.
Heterogeneous Mixtures • A mixture in which the components are not uniform throughout.
Heterogeneous mixtures consist of two or more phases (layers, parts, phases of matter, etc).
Examples – Heterogeneous Mixtures • Fruit Salad • Red Beans and Rice • Jelly Beans • Toy Boxes • Jelly • Students in a Classroom
Homogeneous Mixtures • A mixture in which the composition is uniform throughout.
Homogeneous mixtures must consist of only one phase (layer, parts, phases of matter, etc).
Examples – Homogeneous Mixtures • Jello • Sweet Tea • Melted Cheese • Salt Water
Solutions • Another name for a homogeneous mixture is a solution. • A solution is a homogeneous mixture consisting of a solute dissolved in a solvent.
Solute • The substance dissolved in the other substance.
Solvent • The substance that the other substance is dissolved in.
Example • When you make a glass of sugar water, you take a 4 cups of sugar and dissolve it in 1 gallon of water. • What is the solute?
Example • When you make a glass of sugar water, you take a 4 cups of sugar and dissolve it in 1 gallon of water. • What is the solute? Sugar • What is the solvent?
Example • When you make a glass of sugar water, you take a 4 cups of sugar and dissolve it in 1 gallon of water. • What is the solute? Sugar • What is the solvent? Water • What is the solution?
Example • When you make a glass of sugar water, you take a 4 cups of sugar and dissolve it in 1 gallon of water. • What is the solute? Sugar • What is the solvent? Water • What is the solution? Sugar-Water
Strength of Solutions • The solubility is the amount of solute that can be dissolved in a given amount of solvent at any one temperature. • A solution is said to be unsaturated as long as more solute can be dissolved.
Dilute or Weak Solution - only a small amount of solute compared to solvent.
Concentrated Solution - A relatively large amount of solute to solvent.
Saturated Solution –The concentration of the solute in solution is the maximum possible at that temperature and pressure.
Supersaturated Solution -- a solution that contains more dissolved substance than does a saturated solution; • An example of supersaturated solution is carbonated water. If you shake the bottle, the solution will undissolve the carbonation.
Factors Effecting Solutions • Solubility is the ability of the solvent (water) to dissolve the solute (sugar). • Temperature, Pressure, and polarity of the solvent affect the solvents ability to dissolve the solute.
Increasing Temperature increases solubility. • Increasing Pressure increases solubility. • Changing a solvent can also increase solubility. • If the solute is polar, the solvent needs to be polar also. • If the solute is non-polar, the solvent needs to be non-polar as well.
Separating Mixtures • Differences in physical properties can be used to separate mixtures.
Filtration • The process that separates a solid from a liquid in a heterogeneous mixture is called filtration.
Example • How would I separate beans from a jar filled with water?
Distillation • Distillationhappens when one liquid is separated from another based on boiling points. The first liquid is boiled off, condensed, and then collected as a liquid.
