Catalyzing thoughts: 1. How are ionic compounds different from covalent compounds when dissolved in water?

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1 Name: Period: Date: General Chemistry UNIT 13: Acids and Bases Lesson 1: Theories of Acids and Bases! By the end of today, you will have an answer to: How are we able to determine which substances are acids and bases? Do Now: Blast From the Past Catalyzing thoughts: 1. How are ionic compounds different from covalent compounds when dissolved in water? 2. What is molarity? 3. What is the concentration of a 2 L containing 6 moles of KNO 3. (No calculator needed)

2 What defines an acid or a base? A fun-chemistry activity! Activity: What do acids and bases look like at the particulate level? You will be looking for: 1. Common patterns in terms of the ions that are present 2. How much of the substance becomes turns into ions when dissolved 3. How molarity impacts # of particles present in the Procedures: You will be using cards that represent various s of acids, bases, or neither. Each card represents an aqueous. No water molecules are shown because there are so many of them approximately 140, 000 per square inch! 1. Sort the cards into three groups based on the features listed above. Write the card number, molarity, chemical formula, and chemical name for each. Group 1 Group 2 Group 3 2. What do the s in each of the three groups have in common? Group 1: Group 2: Group 3:

3 3. Fill in the table with the chemical formula of the substance dissolved and the ions in the. Solution Number Name Molarity and Chemical Formula Cations Anions 1 Hydrochloric acid M HCl H + Cl Solutions 1, 2, and 3 each contain hydrochloric acid. How are they different? 6. Hydrochloric acid is a strong acid, while formic acid and acetic acid, are weak acids. Use this information and the cards to try and explain the difference between a weak acid and a strong acid. 7. What do all the s with the word acid have in common? 8. Solutions with OH ions are called basic. Which s are basic? 9. Solutions 6, 7, 8, and 12 are neutral. What do you think this means? PUT IT ALL TOGETHER: Based on your observations of the cards, provide your own definition of an acid and base.

4 CHALLENGE: Solution 11 is the result of dissolving ammonia, NH 3, in water. There are no O atoms in the molecule. How is it possible that the is basic (where do the OH ions come from?) Take Home Points: ACIDS BASES Common properties Arrhenius Definition KEY WORDS ph value Hydrogen ion (H + ) Hydronium ion (H 3O + ) Hydroxide ion (OH ) What happens when dissolved in water? Reference Table Examples Alternate Theory (Brønsted-Lowry)

5 Name: Pd: Date: General Chemistry HW 13.1 Acid and Base Theories 10 points In-class Practice: Directions: Answer the following questions based on your knowledge of chemistry. 1. Which substance is an Arrhenius base? Explain (1) CH 3OH (2) CH 3Cl (3) LiOH (4) LiCl 2. Which compound is an Arrhenius acid? Explain (1) CAO (3) K 2O (4) NH 3 (1) hydroxide ions as the only negative ions (2) hydroxide ions as the only positive ions (3) hydronium ions as the only negative ions (4) hydronium ions as the only positive ions 4. An Arrhenius acid has (1) only hydroxide ions in (2) only hydrogen ions in (3) hydrogen ions as the only positive ions in (4) hydrogen ions as the only negative ions in 5. Which compound releases hydroxide ions in an aqueous? (1) CH 3COOH (3) CH 3OH (4) KOH 3. The compound NaOH (s) dissolves in water to yield Name: Pd: Date: General Chemistry HW 13.1 Acid and Base Theories 10 points In-class Practice: Directions: Answer the following questions based on your knowledge of chemistry. 1. Which substance is an Arrhenius base? Explain (1) CH 3OH (2) CH 3Cl (3) LiOH (4) LiCl 3. The compound NaOH (s) dissolves in water to yield (1) hydroxide ions as the only negative ions (2) hydroxide ions as the only positive ions (3) hydronium ions as the only negative ions (4) hydronium ions as the only positive ions 2. Which compound is an Arrhenius acid? Explain (1) CAO (3) K 2O (4) NH 3 4. An Arrhenius acid has (1) only hydroxide ions in (2) only hydrogen ions in (3) hydrogen ions as the only positive ions in (4) hydrogen ions as the only negative ions in 5. Which compound releases hydroxide ions in an aqueous? (1) CH 3COOH (3) CH 3OH (4) KOH

6 6. Which Lewis electron-dot diagram correctly represents a hydroxide ion? Work hard. Be nice. 8. Which statement describes an alternate theory of acids and bases? (1) Acids and bases are both H + acceptors (2) Acids and bases are both H + donors. (3) Acids are H + acceptors, and bases are H + donors. (4) Acids are H + donors, and bases are H + acceptors. 7. Which ion is the only negative ion produced by an Arrhenius base in water? (1) NO 3 - (2) Cl - (3) OH - (4) H - 9. The only positive ion found in H 2SO 4 (aq) is the (1) ammonium ion (2) hydronium ion (3) hydroxide ion (4) sulfate ion 10. Which two formulas represent Arrhenius acids? (1) CH 3COOH and CH 3CH 2OH (2) HC 2H 3O 2 and H 3PO 4 (3) KHCO 3 and KHSO 4 (4) NaSCN and Na 2S 2O 3 6. Which Lewis electron-dot diagram correctly represents a hydroxide ion? 7. Which ion is the only negative ion produced by an Arrhenius base in water? (1) NO 3 - (2) Cl - (3) OH - (4) H - 8. Which statement describes an alternate theory of acids and bases? (1) Acids and bases are both H + acceptors (2) Acids and bases are both H + donors. (3) Acids are H + acceptors, and bases are H + donors. (4) Acids are H + donors, and bases are H + acceptors. 9. The only positive ion found in H 2SO 4 (aq) is the (1) ammonium ion (2) hydronium ion (3) hydroxide ion (4) sulfate ion 10. Which two formulas represent Arrhenius acids? (1) CH 3COOH and CH 3CH 2OH (2) HC 2H 3O 2 and H 3PO 4 (3) KHCO 3 and KHSO 4 (4) NaSCN and Na 2S 2O 3

7 Name: Date: Chemistry HW 13.1 Theories of Acids and Bases Work hard. Be nice. Pd: General 20 points SUMMARY OF THE LESSON: [10 points] ON A SEPARATE SHEET OF PAPER in a coherent, well-written paragraph Describe the common properties of acids and bases. Explain what happens to acids and bases when they are dissolved in water. Describe the definitions of Arrhenius and Brønsted-Lowry definitions of acids and bases. Explain the effect molarity has on an acid or a base Explain the difference between a strong and weak acids or bases. REGENTS PRACTICE: [3 points] 1. According to one acid-base theory, water acts as an acid when an H 2O molecule (1) accepts an H + ion. (3) accepts an H - (2) donates an H + ion. (4) donates an H - 2. Which compound yields H + ions as the only positive ions in an aqueous? (1) KOH (3) CH 3OH (2) NaOH (4) CH 3COOH --Explain your reasoning behind your choice in #2. [1] CRITICAL THINKING: [5 points] ON A SEPARATE PIECE OF PAPER The acid inside your stomach is approximately 100,000 times more acidic than pure drinking water. It is composed mainly of a.16 M of HCl. Certain people have stomachs that produce too much acid. There are a couple of different treatments for this. Using your knowledge of acids and bases explain them. 1) Antacids like Rolaids or Tums contain weak bases that are swallowed and enter your stomach. 2) Drugs like Prilosec contain proton-pump inhibitors. They stop the stomach from pumping out H + ions. TURNED IN COMPLETE AND ON-TIME [2 points]- STUDY FOR YOUR QUIZ TOMORROW!