IONIC COMPOUNDS: ACIDS AND BASES

1. IONIC COMPOUNDS:ACIDS AND BASES Chapter 8 - CP

2. Properties of Acids and Bases – Journal 1 • SILENTLY, Read and Highlight the 8.3 and 8.4 part of the Worksheet from the back table, THEN make flashcards for section 8.3 and 8.4 vocabulary. • I will be coming around with samples for you to taste. Classify each of the liquids as an Acid, Base or Neutral based on what you learn about the characteristics of acids and bases in your reading.

3. Acids and Bases • Acids and Bases are Compounds that have very distinct properties. HCl + H2O  H3O 1+ +Cl 1- NaOH + H2O  Na 1+ + OH 1- + H2O

4. WATER Before understanding Acids and Bases, you must understand water. • It is a polar molecule. Like a magnet. - - + +

5. WATER • It is a polar molecule. WHY??? Oxygen pulls on the electrons more than Hydrogen does. Oxygen = Higher ionization energy. - - + +

6. WATER Because water is POLAR (negative side and positive side), what types of compounds will it DISSOLVE easily? CHARGED http://www.northland.cc.mn.us/biology/Biology1111/animations/dissolve.html - - + +

7. Acids • Acids: compounds that produce HYDRONIUM IONS when dissolved in water. • HCl + H20  H3O1+ +Cl1- • Written also as: HCl  H1+ +Cl1-

8. Acids When HCl is put in water, a Hydronium ion, H3O1+ (hydrogen ion, H1+) is formed. Why might acids be referred to as “PROTON DONORS”?

9. Acids: IONIZATION Acids ARE “PROTON DONORS” http://www.learning.gov.sk.ca/branches/elearning/tsl/resources/subject_area/science/chem_30_resources/lesson_8/acids_and_bases.shtml

10. Acids • Characteristics of Acids • Taste Sour • React Strongly with Metals and Carbonates (in soil and rocks) • Burn skin • Conduct electricity in water • Turn blue litmus paper red

11. Common Acids Acetic acid CH3COOH Vinegar Carbonic acid H2CO3 Carbonated beverages Hydrochloric acid HCI Digestive juices in stomach Nitric acid HNO3 Fertilizer production Phosphoric acid H3PO4 Fertilizer production Sulfuric acid H2SO4 Car batteries

12. Bases • Bases: ionic compounds that produce HYDROXIDE IONS when dissolved in water. NaOH  Na 1+ + OH 1-

13. Bases: DISSOCIATION Bases are Ionic compounds that break apart (dissolve) in water to form a negatively chargedhydroxide ion (OH 1-). Why might bases be referred to as “PROTON ACCEPTORS”? http://web.umr.edu/~gbert/ANIMATED/Asoly.HTML

14. Bases http://www.learning.gov.sk.ca/branches/elearning/tsl/resources/subject_area/science/chem_30_resources/lesson_8/acids_and_bases.shtml Bases ARE “PROTON ACCEPTORS” http://www.mhhe.com/physsci/chemistry/animations/chang_7e_esp/acm2s2_1.swf

15. Bases • Characteristics of Bases • Taste bitter • Feel Slippery • Burn your Skin • Conduct electricity in water • Turn red litmus paper blue

16. Common Bases Aluminum hydroxide Al(OH)3 Deodorant, antacid Calcium hydroxide Ca(OH)2 Concrete, plaster Magnesium hydroxide Mg(OH)2 Antacid, laxative Sodium hydroxide NaOH Drain cleaner, soap production

17. Strength of Acids and Bases – Journal 3 • Fill in the “Identifying Acids and Bases” Worksheet. • How can you tell how strong an acid or a base is? • What do the numbers on the scale below mean? • What does “0” represent? What does “7” represent? What does “14” represent?

18. Strength of Acids and Bases Which would you say is MORE acidic: • battery acid • Or milk? WHY is battery acid MORE ACIDIC?

19. Strength of Acids and Bases • MORE hydronium (H3O 1+)ions. • How many hydronium ions are in the strong acid? In the weak acid?

20. Strength of Acids and Bases • Chemists use a number scale from 0 to 14 to describe the concentration (amount of) hydronium (H3O 1+)ions in a solution. • This is the pH Scale.

21. Strength of Acids and Bases • The pH of a solution is a measure of the hydronium ion (H3O 1+)concentration.

22. Strength of Acids and Bases • Neutral substances have a value of 7 • Their number of hydronium ions equal their number of hydroxide ions.

23. Strength of Acids and Bases • Distilled water is neutral. • It’s hydronium ions equal it’s hydroxide ions This is because water ionizes slightly.

24. Strength of Acids and Bases • Acids have a pH value of LESS THAN 7 • Bases have a pH value of MORE THAN 7 • What is the strongest acid on the chart? • What is the strongest base? • What is the weakest acid? • The weakest base?

25. Properties of Acids and Bases – Journal 2 • Come in and take out your homework (pH Lab). • Fill in the Acids and Bases practice from the back table. • Read and answer the questions on the Neutralization Worksheet from the back table.

26. Reactions between Acids and Bases • WhenbasesREACT with acids, the process is calledNEUTRALIZATION.

27. Reactions between Acids and Bases • When bases REACT with acids, the process is calledNEUTRALIZATION. • They react to form a salt and water (& HEAT) • Hydrochloric Acid + Sodium Hydroxide Water + Table Salt HCl + NaOH  H2O + NaCl Take out the neutralization worksheet.

28. Common Salts Sodium chloride NaCl Food flavoring, preservative Sodium carbonate Na2CO3 Used to make glass Potassium chloride KCl Used as a salt substitute to reduce dietary intake of sodium Potassium iodide Kl Added to table salt to prevent iodine deficiency Magnesium chloride MgCl2 De-icer for roads Calcium carbonate CaCO3 Chalk, marble floors, and tables Ammonium nitrate NH4NO3 Fertilizer, cold packs

29. Properties of Acids and Bases – Journal 5 • Come in, take out your homework, and get your LAB sample. • Write an equation that shows NEUTRALIZATION. Include the names of the REACTANTS and PRODUCTS. • What is the range of the pH scale? The range for acids? Bases? Neutral? • What is the strongest Acid value? Base value? What would be a weak acid? Weak base?