3. Acids and Bases

Would the following reactions go to the right or the left? Draw the products and label ALL species. Provide the full mechanism.

Would the following reactions go to the right or the left? Draw the products and label ALL species. Provide the full mechanism.

Would the following reactions go to the right or the left? Draw the products and label ALL species. Provide the full mechanism.

Would the following reactions go to the right or the left? Draw the products and label ALL species. Provide the full mechanism.

Which anion in each pair would you expect to react more quickly with H⁺ ?

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If reacted with a strong base, which of the labeled protons would you expect to be removed first?

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In each pair, choose the most acidic compound. Justify your answer. The most acidic proton in each compound has been indicated.

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Rationalize the difference in pKₐ values for the two hydroxyl groups.

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p-Nitrophenol (pKₐ = 7.2) is ten times more acidic than m-nitrophenol (pKₐ = 8.4) Explain. [This concept is the subject of Section 24.2.1 in the chapter on benzene.]

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Which is the most stable base in each pair?

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Which is the most acidic compound in each pair?

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Which is the most acidic compound in each pair?

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Using qualitative reasoning for the acid–base reactions shown,

(i) which is stronger, the base or the conjugate base?

(ii) Which side of the reaction is favored?

(iii) Would you expect a greater than or less than 1?

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Rank the following alcohols in order of descending pKₐ value. Explain your ranking.

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Which of the following indicated atoms would you expect to be most basic?

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The nitrogen screened in purple in Figure 4.43 is not protonated at physiological pH. Why?

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Which is the most stable base in each pair?

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(••) Identify the stronger base in each pair. Explain your choice. Citing pKₐ values is not an acceptable answer.

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Imidazole is a heteroaromatic base. Which nitrogen, a or b, is most basic?

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Without using pKₐ values, pick out the least reactive (most stable) base in each pair. Explain your answer.

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Using qualitative reasoning for the acid–base reactions shown, 

(i) which is stronger, the acid or the conjugate acid? 

(ii) Which side of the reaction is favored? 

(iii) Would you expect a greater than, equal to, or less than 1?

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Identify the most stable conjugate base in each pair. Tell which structural features you analyzed and why you weighted them as you did in picking one answer.

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Identify the most stable conjugate base in each pair. Tell which structural features you analyzed and why you weighted them as you did in picking one answer.

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Identify the most acidic proton in each pair. Tell which structural features you analyzed and why you weighted them as you did in picking one answer. [Always start by drawing the conjugate base.]

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Identify the most acidic proton in each pair. Tell which structural features you analyzed and why you weighted them as you did in picking one answer. [Always start by drawing the conjugate base.]

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Which acid in each pair would you expect to more readily donate a proton to a basic compound?

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Why is the value of protonated hydroxylamine (6.0) so much lower than the value of a protonated primary amine such as protonated methylamine (10.7)?

(••) In light of your answers to Assessments 24.54 and 24.55, rank the following based on the rate of protonation of the alkene (1 = most basic, 6 = least basic). [Ignore the fact that the alkene may not be the most basic site in the molecule.]

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(•••) Consider the following drugs used to treat the indicated diseases. Would you expect the activity of these drugs to be impacted by a patient taking other medicines for acid reflux disease?

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