Presentation on theme: "Mixtures. Look at the pictures: Other examples for teacher Air (N 2, O 2, CO 2, Ar, other gases) – gas in gas Soda pop (CO 2 in water) – gas in liquid."— Presentation transcript:
Other examples for teacher Air (N 2, O 2, CO 2, Ar, other gases) – gas in gas Soda pop (CO 2 in water) – gas in liquid Sea water (NaCl and other salts in water) – solid in liquid Dental amalgams (mercury in silver) - liquid in solid Alloys (brass, (Cu/Zn), solder (Sn/Pb) – solid in solid
Answer following questions: What is different on this picturer? What substances are this mixtures? Write a componets of this mixtures. How to prepare homogenized milk and mayonnaise? What conditions are necessary for origine this mixtures?
What is on the pictures? Think: Mix them and say what will originate?
Students experiment: Take two of these materials and mixed them and say what originate from them (students make). Teachers experiment (frontal experiment) a) Sulphur and iron – mixed and separated by magnet b) Sulphur and iron – mixed, heat up Discuss about conditions, colours, phases, etc.
Description for teachers The student will learn about different types of mixtures Vocabulary: mixture 1 solution, solute, solvent suspension emulsion colloid 2 Homogenous Heterogeneous
Teacher Background A mixture is a combination of substances. All solutions, suspensions, emulsions, and colloids are types of mixtures. A solution is a liquid that contains a dissolved substance – solid, liquid, or gas. The solvent is the liquid in which the substance is dissolved. The solute is the substance dissolved in the liquid. Solutions do not have to be liquid. There are also solid solutions, such as glass, and gaseous solutions, such as air. An emulsion is a suspension of small globules of one liquid in another. Water is a polar substance. Water is miscible with other polar liquids which dissolve in water. Oil is a nonpolar substance. Oil is miscible with other nonpolar liquids which dissolve in oil, but not all oils dissolve in each other. Oil and water do not mix; they are immiscible; they make an emulsion. A suspension is a mixture of a solid in a liquid where the solid does not dissolve in the liquid but stays temporarily suspended in the liquid until gravity pulls it down. A colloid is a solution containing tiny undissolved particles that permanently remain suspended in the liquid, such as homogenized milk and mayonnaise.
Experiment: Use microscope and observe this mixtures. Write the characteristics of this mictures (colour, texture, structure, components, etc.).
Practical use Most foods, and even cosmetics are mictures of one type mentioned above or the other. They are made of different substances that when put together. Find examples of mixtures in practical live. (Use TV, web, …)