1. T. Sudarat Khampa

2. Acids Latin word ‘acidua’ : sour Has a sour test Has a pH value less than 7 Has a corrosive nature Turns blue litmus paper red Reacts with reactive metals to produce hydrogen gas.

3. example Acid Soft drinkCarbonic acid TomatoSalicylic acid BatterySulfuric acid GrapeTartaric acid Ant/BeeFormic acid VinegarAcetic acid LemonCitric acid YoghurtLactic acid AppleMalic acid OrangeCitric acid

4. Identifying the property of acid procedureobservationinference Lemon tested with tonguesour testAcid test sour - Dipped pH paper to dilute hydrochloric acid -Compare with color chart pH value of 2Acid has pH value less than 7 Drop concentrated hydrochloric acid into a filter paper It has hole in it. Acid has corrosive

5. Identifying the property of acid procedureobservationinference - Dipped red and blue litmus papers to dilute hydrochloric acid blue litmus paper red Acid turns blue litmus paper red - placed magnesium ribbon in hydrochloric acid - test gas with a lighted spinter. Gas give out a squeaky ‘pop’ Acid react magnecium to produce hydrogen gas.

6. Alkali Has bitter test Has a pH value greater than 7 Terns red litmus paper blue Has a soapy feel Has corrosive nature Reacts amonium salts to release ammonia when heated.

7. example Bleach Oven /Glass cleaners Detergent Soap Some Shampoo Ammonium solution Sodium hydroxide solution Potassium hydroxide solution In the laboratory In your life

8. Identifying the property of alkali procedureobservationinference Touched dilute sodium hydroxide solution It fell soapy and slippery Alkali has soapy feel - Dipped pH paper to sodium hydroxide solution -Compare with color chart pH value of 10Acid has pH value more than 7

9. Identifying the property of alkali procedureobservationinference Drop concentrated sodium hydroxide into a filter paper It has hole in it. Alkali has corrosive - Dipped red and blue litmus papers to dilute sodium hydroxide red litmus paper turns blue Alkali turns red litmus paper blue

10. pH IndicatorspH Indicators pH scale

11. pH IndicatorspH Indicators Change color when dipped in acids or alkalis

12. pH IndicatorspH Indicators Universal indicator

13. Uses of acids Citric acid : give a sour test to food and drinks : as a polishing agent for metals Tartaric acid : flavoring food and drinks : produce fruit/health salts Benzoic acid : preservative in food ; sauces

14. Uses of acids Ascorbic acid : increase body resistance and (vitamin C) prevent scurvy Formic acid : coagulate latex Acetic acid : used as Vinegar : preservative in food ; pickles : to produce paints, plastics, rayon

15. Uses of acids Sulfuric acid : used in car battery and fire extinguishers Hydrochloric acid : clean metals : cleansing agent in toilet cleaners Nitric acid : to produce fertilizers, dye, explosive

16. Uses of alkalis Sodium hydroxide : to produce soap, detergent, plastic, rayon Calcium hydroxide : to produce cement, mortar, soda lime, glass

17. Uses of alkalis Amonium : - prevent coagulation of latex - glass cleaning agent - produce nitric acid and fertilizer Magnesium hydroxide : produce medicine; - antacids - magnesia milk - Epsom salt