1. For each of the species below, identify the most acidic proton and provide the structure of the corresponding conjugate base. You might want to draw detailed Lewis formulas in some cases.
2. For each of the species below, identify the basic atom and provide the structure of the corresponding conjugate acid. You might want to draw detailed Lewis formulas in some cases.
3. Fill in the reactants or products for the following acid-base reactions. Keep in mind that in line-angle formulas hydrogens are not shown. When in doubt, write complete Lewis structures. Abbreviations used: Ph=phenyl (a benzene ring attached to a carbon chain)
4. Arrange the substances by order of acidity or basicity as indicated. You may use pKa tables, periodic tables, or any other tools available to you (except for your cell phone).
5. Circle the side favored by equilibrium in the following acid-base reactions.
6. The conjugate acid of ammonia, NH3, is:
A) NH4 + B) NH2OH C) NH2 - D) none of the above
7. Methanesulfonic acid, CH3SO3H, has a pKa of -7 while ethanol, CH3CH2OH, has a pKa of 15.9. Which is the stronger acid and what accounts for this large difference in relative acidity?
8. Would you predict trifluoromethanesulfonic acid, CF3SO3H, to be a stronger or weaker acid than methanesulfonic acid, CH3SO3H? Explain your reasoning.
9. Consider the species CH3O-, NH2 -, and CH3COO-. Rank these ions in order of increasing basicity, and explain your rationale.
10. The Ka of formic acid is 1.7 x 10-4. The pKa of formic acid is __________.
A) 1.7 B) 10.3 C) 4.0 D) 3.8 E) -2.3
11. Provide the structure of the conjugate base of phenol (shown below) and all its resonance forms.
12. Rank the following in order of increasing acidity: CH3OH, HCl, NH3, and CH4.
13. Rank the following in order of increasing basicity: CH3O-, H2N-, H2O, and NH3.
14. When methanol (CH3OH) acts as a base, its conjugate acid is __________. A) CH4OH B) CH3OH2+ C) CH4O+ D) CH3O- E) -CH2OH
15. Which of the following pairs of bases lists the stronger base first?
A) H2O > HO-
B) H2N- > CH3COO-
C) CH3COO- > HO-
D) I- > Cl-
E) HO- > H2N-
16. Draw the structure of the conjugate acid of acetone (CH3COCH3).