2. ACIDS, BASES, & SALTS

3. ACIDS Contain hydrogen ions, H + also called hydronium ions, H 3 O + Taste sour (remember not to taste chemicals as a rule) Dangerous to skin Formed from hydrogen and a non metal

4. Acids - Examples Hydrochloric acid HCl – cleans metals; stomach acid Nitric acid HNO 3 – component of fertilizer Sulfuric acid H 2 SO 4 – car batteries; plastics. This is the single most produced chemical.

5. Acids - Examples Lactic acid HC 3 H 5 O 3 – milk, muscle cramps Citric or Ascorbic acid HC 6 H 7 O 7 – fruit juice, flavored candy Carbonic acid H 2 CO 3 – soda pop Acetic acid HC 2 H 3 O 2 – vinegar, photographic chemicals

6. Bases, Alkalines, Antacids Contain hydroxide ions OH - Taste bitter Feel slippery because they dissolve the fats in skin Good grease cleaners Contain a metal and a hydroxide group

7. Bases - Examples Ammonium hydroxide NH 4 OH – ammonia, found in many cleaners Sodium hydroxide NaOH – lye, most common base, found in soap and drain cleaner Magnesium hydroxide Mg(OH) 2 – milk of magnesia Calcium hydroxide Ca(OH) 2 – lime water, found in cement Sodium bicarbonate NaHCO 3 – baking soda, component of antacids

8. Indicators An indicator is a chemical that changes color to show whether a solution is an acid or base.

9. Examples of Indicators Litmus Red in an Acid Blue in a Base Phenolphthalein Clear in an Acid Pink in a Base There are many, many others.

10. Litmus Paper On the left in KOH and on the right in HCl.

11. Phenolphthalein On the left in an acid and on the right in a base.

12. Bromothymol Blue On the left in an acid and on the right in a base.

13. pH How strong is that acid or base?