9. COMPOUNDS are homogeneous materials with definite composition which may be decomposed into two or more simpler substances by chemical change.

10. ACIDS & BASES ACIDS are characterized by: a)Sour taste b)Turns blue litmus paper to red c)React with bases to form salts & water d)React w/ active metals to produce hydrogen gas. e)“burns” your skin: corrosive f)pH value : 0 to 6.9 BASES (also ALKALI) characterized by: a)Turns red litmus paper to blue b)Slippery and soapy feel c)Bitter or biting taste d)React with acids to form salts and water e)Turns fats into soaps f)pH value : 7.1-14

12. ELECTROLYSIS is a chemical process by which an electric current is applied into their constituent elements that changes the composition of the materials.

15. SOLUTIONS are homogeneous mixture that is composed of a solute and a solvent. The new combination has only one phase.

16. SUSPENSIONS are heterogeneous mixtures that have the biggest particles.

17. COLLOIDS are heterogeneous mixture in which one substance is dispersed evenly throughout another

18. Classify the following matter : Homogeneous, Heterogeneous, Compound or Element Cement Dust free air 22 karat Gold bracelet Pure NaCl Al metal Dry sugar + flour Filtered Sea water Na metal Brass Homogeneous mixture Heterogeneous mixture Homogeneous mixture Compound Element Heterogeneous mixture Homogeneous mixture Element Homogeneous mixture

23. DECANTATION is the separation of mixtures with different densities. CHROMATOGRAPHY is the separation of components in a mixture based on the affinity for the solvent.

25. What method will you use to separate immiscible liquids? (Oil and water) It can be separated using a SEPARATING FUNNEL. This apparatus allows the lower, more dense liquid to be drawn off at the bottom, leaving the less dense liquid in the funnel. An older and less satisfactory technique is the process of DECANTING where the top layer is simply poured off.

26. Problem: Aquarium B has to be filled with some water samples brought from the coast. However, this sample is suspected to be contaminated with a dissolved solid and a dissolved liquid. If the water is not purified, it cannot be used by the fish. Task: Obtain a clean sample of water and show the pollutants that were affecting the water. Questions:  What types of mixtures are observed in the aquarium?  What is meant by physical means of separation? What is the difference with chemical means?

27. THE END…..