University:
Eastern Kentucky University
Course:
CHE 361 | Organic Chemistry I
Academic year:

2021
Views:

325

Pages:

4
Author:

Carissa Thomas

Chapter 2 Acids and Bases Review Questions Connect Homework Assignment (Organic Chemistry Janice Smith 5th ed. Textbook) 1. Draw the products of the following acid-base reaction. + Conjugate acid Conjugate base 2. Classify each of the following compounds as an acid, base, or both. Be sure to answer all parts. CH3CH2OH – both acid and base CH3CH2CH2CH3 – acid CH3CO2CH3 – both acid and base 3. Consider two acids: HCO2H (formic acid, pKa = 3.8) and (CH3)3CCO2H (pivalic acid, pKa = 5.0). Which acid is the stronger acid? Select the single best answer. A. Pivalic acid B. Formic acid 4. Consider two acids: (CH3)3CCO2H (pivalic acid, pKa = 5.0) and HCO2H (formic acid, pKa = 3.8). Which acid forms the stronger conjugate base? Select the single best answer. A. Pivalic acid B. Formic acid 5. Select the three most acidic hydrogen atoms in lactic acid, CH3CH(OH)CO2H, and rank them in order of decreasing acidity. Explain your reasoning. Be sure to answer all parts. Part 1 A. B. C. D. CH3 COOH Alcohol OH α - CH Part 2 Most acidic b Least acidic a c b c a Part 3 This ranking is explained by: A. Electronegativity and resonance makes the COOH most acidic; the conjugate base of the CH3 has no stabilization, and so is least acidic. B. Electronegativity makes the alcohol OH most acidic; the conjugate base of the α−CH has negatively charged C, and so is least acidic. C. Resonance makes the α−CH most acidic; the conjugate base of the CH3 has no stabilization, and so is least acidic. D. Electronegativity and resonance makes the COOH most acidic; the conjugate base of the alcohol OH has no stabilization, and so is least acidic. 6. Which compound in the following pair is the stronger acid? Select the single best answer. A. B. 7. Click on the “draw structure” button to launch the drawing utility. What is the conjugate base of A? Answer: 8. The pKa of three different C―H bonds is given below. Explain the observed trend in pKa. Select the single best answer. A. Higher pKa values result from better stabilization of the conjugate base by electronegative elements. B. Higher pKa values result from better resonance stabilization of the conjugate base. C. Lower pKa values result from better resonance stabilization of the conjugate base. D. Lower pKa values result from the lower acidity of the C―H bond. 9. Draw the products formed when 2−propanol [(CH3)2CHOH], the main ingredient of rubbing alcohol, is treated with NaH. Be sure to answer all parts. conjugate base conjugate acid 10. Draw the products formed when 2−propanol [(CH3)2CHOH], the main ingredient of rubbing alcohol, is treated with H2SO4. + conjugate acid conjugate base 11. Draw the product formed when the Lewis acid reacts with the Lewis base (CH3)2NH. Click the "draw structure" button to launch the drawing utility. Answer: 12. Draw the product of the Lewis acid-base reaction. Label the electrophile and nucleophile. Be sure to answer all parts. + nuleophile electrophile 13. Draw the product of the Lewis acid-base reaction. Label the electrophile and nucleophile. electrophile nucleophile