Given that the indicated pK_a values correspond to the acid dissociation reactions shown, calculate the ratio of acid to conjugate base for the reactions shown.

(a)

Given that the indicated pK_a values correspond to the acid dissociation reactions shown, calculate the ratio of acid to conjugate base for the reactions shown.

(b)

Hydrogen gas (H₂) has a relatively high pK_a value. Is it a stable or unstable acid? Do you expect it to participate in acid–base reactions?

How do you know that a proton with a low pK_a value is acidic (besides 'I just remember')?

If a base has a conjugate acid with a high pK_a value, is it stable or unstable? How do you know this is true (besides 'I just remember')?

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 K_eq greater than, equal to, or less than 1?

(a)

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 K_eq greater than, equal to, or less than 1?

(b)

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 K_eq greater than or less than 1?

(a)

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 K_eq greater than or less than 1?

(c)

Calculate K_eq for these acid–base reactions.

(c)

Calculate K_eq for these acid–base reactions.

(d)

For each indicated proton, suggest an approximate pK_a value from Table 4.5. Rationalize your choice.

(b)

For each indicated proton, suggest an approximate pK_a value from Table 4.5. Rationalize your choice.

(d)

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(b)

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(c)

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(d)

For the bases shown, draw the conjugate acid and identify a pK_a value from Table 4.5 that would help you accurately estimate its stability.

(e)

Without using pK_a values, pick out the more acidic compound in each pair. Explain your answer.

(a)

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

(a)

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

(a)

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

(b)

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

(c)

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

(a)

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

(b)

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

(a)

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

(b)

Rationalize the rather large difference in pK_a values for the two carboxylic acids shown.

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

Rank the following amines in order of their basicity (strongest base = 1 ; weakest base = 6).

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