Lesson Acids and Bases Science Differentiation in action

Lesson: Acids and Bases

Science Differentiation in action All acids have a sour taste. Carbonic acid Citric acid

Science Differentiation in action Some acids are corrosive. What elements are contained in these acids? Sulfuric acid. (H 2 SO 4) Hydrochloric acid. (HCl)

Science Differentiation in action Which hazard symbol represents corrosive? A B C

Science Differentiation in action How would we test for an acid? Try some experiments. Use litmus paper. What did you find out? red. Acids turn blue litmus paper ____

Science Differentiation in action Bases are the opposite of acids. Toothpaste Soap Cleaning agents

Science Differentiation in action Strong bases include: Sodium hydroxide (Na. OH) Calcium hydroxide Ca(OH)2 What elements are contained in these bases?

Science Differentiation in action Strong bases include: NONCORROSIVE Sodium hydroxide is also called caustic soda because it is corrosive. Calcium hydroxide is also called limewater.

Science Differentiation in action Bases that dissolve in water are called: Alkalis So ______ alkalis are bases soluble in water.

Science Differentiation in action How would we test for a base or an alkali? Try some experiments. Use litmus paper. What did you find out? blue Alkali turn red litmus paper ____.

Science Differentiation in action The strength of acids and bases can be measured on a p. H scale. Each colour represents a number on the p. H scale. Strong acid 1 3 Weak base Weak acid 5 7 9 p. H 7 is neutral. It is not an acid or a base. Strong base 11 12 14

Science Differentiation in action Each colour represents a number on the p. H scale. Strong acid 1 3 Weak base Weak acid 5 7 9 Strong base 11 12 p. H 7 is neutral. It is not an acid or a base. We can measure p. H using universal indicator. 14

Science Differentiation in action Each colour represents a number on the p. H scale. Strong acid 1 3 Weak base Weak acid 5 7 9 Strong base 11 12 14 Now, use universal indicator to find the p. H of some substances.

Science Differentiation in action Review Questions 1. What acid is found in your stomach? 2. Which p. H is neutral? 1 3 5 7 9 11 3. What would you use to measure p. H? 12 14

Science Differentiation in action Question to think about! What happens when you add an acid to a base?