Chapter 9.3 Part 2 Q: What is the chemical formula for the molecules in candy? A: Carbon-Holmium-Cobalt-Lanthanum- Tellurium or CHoCoLaTe Q: What is the chemical formula for the molecules in candy? A: Carbon-Holmium-Cobalt-Lanthanum- Tellurium or CHoCoLaTe

Key concepts: Analyze a solution in terms of its solute and solvent Explain how concentration affects a solution Describe the particles in a suspension Explain how a colloid differs from a solution and a suspension.

Key Vocabulary: Mixture Concentration Solubility Suspension Colloid Solvent Solute Solution

Review of Mixtures: A mixture is a combination of two or more substances that are not chemically combined. How are mixtures different from compounds? – They form a mixture when they don’t chemically react like a compound Think about trial mix or a pizza… – Can you taste the tomato pasta? Meat? What does pure mean? How is this different from an compound? What are some examples of chemical and physical changes?

New Terms for You! Homogenous mixtures Heterogeneous mixtures

Heterogeneous Mixture: Heterogeneous mixtures are those where the substances are not distributed evenly. They usually involve a mixture of a solid in a solid. A mixture of stones in soil is an example of a heterogeneous mixture.

Homogenous Mixture: Homogeneous mixtures are those where the materials are evenly distributed throughout. Homogenized milk is an example.

Solutions: A solution is a mixture that appears to be a single substance. – Composed of particles of two or more substances that are mixed EVENLY among each other. Dissolving: – Process in which particles of a substance separate and spread evenly throughout a mixture This is IMPURE! How is this different from an compound? What are some examples of dissolving? Is it chemical or physical?

Solutions: Composed of 2 things: – Solute: substance that is dissolved Found in the lesser amount – Salt in water Can be soluble – Able to dissolve Can be insoluble – Unable to dissolve – Solvent: substance in which the solute is dissolved This is IMPURE! What are some examples of dissolving? Is it chemical or physical?

Examples of Solutions: Solutions can be liquids or gases – Salt water – Sugar water – Solids in solids (stainless steel) If you look at the side of a quarter, oxygen and other gases in nitrogen. Many familiar metals you can see layers of different metals. Is the coin a solid solution? Explain. Atmosphere: – 78% nitrogen – 21% oxygen – And other gases Think of any? This is IMPURE! Table 2: page 245 READ THIS! Is it chemical or physical?

Solubility: – The ability of the solute to dissolve in a solvent at a certain temperature – Most solids are more soluble in liquids at high temps, but gases are less soluble in high temps (think hot coke) This is when the sugar can’t always be dissolved Hot water dissolves more solute than cold water Are gases more soluble at high or low temperatures?

Graph: What is the solubility of sodium chlorate at 60°C?

Speeding up the dissolving process: To speed up how fast solids will dissolve in liquids, you can: – Mixing – Heating – Crushing Page 247 Hot water dissolves more solute than cold water

Concentration of Solutions: Concentrations: – Dilute: Less solute in the same amount of solvent – Concentrated: More solute in the same amount of sovlent What are some examples that you can think of for this? Sweet vs unsweet tea Try # 1-3 on page 246 Q-tips says, Q: If H-two-O is the formula for water, what is the formula for ice? A: H-two-O-CUBED

Picture:

Particles in Solution Solutions: – Particles are so small NEVER settle out due to how small they are Make sure that you know what an alloy is.. Know the differences between solutions and colloids

Colloids vs. Suspension: Colloid: – A mixture in which the particles are dispersed throughout but are not heavy enough to settle out. – Small and mixed well but not as good as solution – Can’t be filtered but scatter light (the particles) – Examples: Milk, mayo, and deodorant What is a colloid?

Colloids vs. Suspension: Suspension: – A mixture in which the particles are dispersed throughout and are heavy enough to settle out. – Scatter and block light Dirty lake water – Can be filtered – Examples: Salad dressing, medicines, paint What is a suspension? This snow globe contains solid par- ticles that will mix with the clear liquid when you shake it up. But the particles will soon fall to the bottom when the globe is at rest.

Review: What are the solvent and solute in a solution containing 100 grams of ethanol and 3 grams of sucrose? Suppose you add a cup of sugar to hot water and all of the sugar dissolves. Then the water cools and some of the sugar is seen as a solid on the bottom of the beaker. Explain why this happened.

Homework: Workbook pages: – Page : Use your books as you do – Page 249 #5-11 – Begin studying Study guide Workbook pages: – Page : Use your books as you do – Page 249 #5-11 – Begin studying Study guide A neutron walks into a restaurant and orders a couple of cokes. As she is about to leave, she asks the waiter how much she owes. The waiter replies, "For you, No Charge!!!"