1. + Acids and Bases

2. + Examples of Acids?

3. + Examples of Acids lemon, vinegar, grapefruit. pop Lactic Acid found in your muscles Some animals use acid to deter predators eg. Scorpions spray acetic acid from their glands when frightened.

4. + What is an Acid? A substance that produces hydrogen ions when dissolved in water. Acid + Water --> H + ions + other ions Common properties: Taste sour Corrosive React with metals

5. + Examples of Bases?

6. + Examples of Bases Some common bases are Soap, eggs, baking soda, antacids How do these feel? Lidocaine (local anesthetic used at the dentist) Draino

7. + What is a Base? A substance that produces hydroxide (OH – ) ions when dissolved in water. Base + Water --> OH – ions + other ions Common properties: Taste bitter Feels slippery

8. + Mixing Acids and Bases When we mix acids and bases, this is called a neutralization reaction Acid + Base --> water + salts H + (aq) + OH – (aq)

9. + Can you have stronger acids than others? Is lemon juice a stronger acid than pop? Can we measure this?

10. + pH Scale A numeric scale that is used for identifying if a solution is acidic, basic, or neutral Typically ranges from 0 to 14 Acidic Solution: pH < 7 Lemon juice pH = 2 Tomato juice pH = 4 Basic Solution: pH > 7 Eggs pH = 8 Soap pH = 10 Neutral Solution: pH = 7 Pure Water

11. + Identifying Acids and Bases Acid-base Indicators: a chemical that is a characteristic colour when in the presence of an acid or a base Example: Red and Blue Litmus Red Litmus: Stays red in acid, but turns blue in base Blue Litmus: Stays blue in base, but turns red in acid

12. + Identifying Acids and Bases Phenolphthalein Colourless from pH of 0 to 8, and then pink from pH 8 to 14. Universal Indicator Different colours at different pH values

13. + Properties of Acids and Bases PropertyAcidBase Taste (CAUTION: Never do this in the lab) SourBitter Touch (CAUTION: Never do this in the lab) Can be corrosiveSlippery Can be corrosive Production of IonsHydrogen ion H + (aq) Hydroxide ion OH – (aq) Reaction with some metalsReacts (and corrodes) them No reaction Electrical Conductivityyes Litmus indicator testBlue litmus turns redRed litmus turns blue pHLess than 7 (<7)Greater than 7 (>7)

14. + https://www.youtube.com/watch?v=ujkuW-0cpNw Pg. 161 # 11 - 16