Question 1

What type of reaction is shown below?  &#10;A) addition&#10;B) substitution&#10;C) elimination&#10;D) rearrangement

Accepted Answer

Addition reactions are when multiple bonds are replaced by another functional group. Substitution reactions are reactions that occur when one functional group is replaced with another functional group. Elimination reactions are reactions that occur when a functional group is replaced with a multiple bond. Rearrangement reactions occur when a molecule rearranges its structure without changing its molecular formula. This reaction involves removing a double bond and replacing it with a Bromine and a Hydrogen; therefore, this is an addition reaction.

Question 2

In the following acid-base reaction, the indicated molecule is a(n) ___ ?  &#10;A) Acid&#10;B) Base&#10;C) Conjugate acid&#10;D) Conjugate base

Accepted Answer

Acids donate or lose a Hydrogen. Bases accept or gain a Hydrogen. Acids and bases by convention are located on the left side of the reaction arrows. Conjugate acids are the bases after they have accepted/added a Hydrogen. Conjugate bases are the acids after they have donated/removed a Hydrogen. Conjugate acids and bases by convention are located on the right side of the reaction arrows. In this reaction, the pyridine accepts a hydrogen from the butanoic acid; therefore it is a base.

Question 3

In the following acid-base reaction, the indicated molecule is a(n) ___ ?  &#10;A) Acid&#10;B) Base&#10;C) Conjugate acid&#10;D) Conjugate base

Accepted Answer

Acids donate or lose a Hydrogen. Bases accept or gain a Hydrogen. Acids and bases by convention are located on the left side of the reaction arrows. Conjugate acids are the bases after they have accepted/added a Hydrogen. Conjugate bases are the acids after they have donated/removed a Hydrogen. Conjugate acids and bases by convention are located on the right side of the reaction arrows. In this reaction, the butanoic acid donates a hydrogen to the pyridine; therefore it is an acid.

Question 4

In the following acid-base reaction, the indicated molecule is a(n) ___ .  &#10;A) Acid&#10;B) Base&#10;C) Conjugate acid&#10;D) Conjugate base

Accepted Answer

Acids donate or lose a Hydrogen. Bases accept or gain a Hydrogen. Acids and bases by convention are located on the left side of the reaction arrows. Conjugate acids are the bases after they have accepted/added a Hydrogen. Conjugate bases are the acids after they have donated/removed a Hydrogen. Conjugate acids and bases by convention are located on the right side of the reaction arrows. In this reaction, the pyridine has accepted a hydrogen from the butanoic acid to become protonated. The protonated pyridine can now donate a hydrogen and has become the conjugate acid.

Question 5

In the following acid-base reaction, the indicated molecule is a(n) ___ .  &#10;A) Acid&#10;B) Base&#10;C) Conjugate acid&#10;D) Conjugate base

Accepted Answer

Acids donate or lose a Hydrogen. Bases accept or gain a Hydrogen. Acids and bases by convention are located on the left side of the reaction arrows. Conjugate acids are the bases after they have accepted/added a Hydrogen. Conjugate bases are the acids after they have donated/removed a Hydrogen. Conjugate acids and bases by convention are located on the right side of the reaction arrows. In this reaction, the butanoic acid has donated its hydrogen to pyridine to become the butonate anion. This anion can now act as a base and is the conjugate base.

Question 6

Which of the following structures are Lewis Acids?  &#10;A) I&#10;B) II&#10;C) III&#10;D) IV&#10;E) I and IV&#10;F) II and III&#10;G) I, III and IV

Accepted Answer

Boron trifluoride and aluminum trichloride both have open p-orbitals that can accept electrons and act as Lewis Acids (electron pair acceptors).

Question 7

Which of the following structures are Lewis Bases?&#10;A) I&#10;B) II&#10;C) III&#10;D) IV&#10;E) I and IV&#10;F) II and IV&#10;G) II, III and IV&#10;

Accepted Answer

Structures II, III and IV all have lone pairs that can donate electrons and act as Lewis Bases (electron pair donors).

Question 8

Using pKa table 3.1, page 111, what is the strongest base? A) H₂O B) Br- C) NH₃ D) OH- E) CH₃CH₂-

Accepted Answer

Using the pKa table, refer to the conjugate base column. The strength of base increases as you go down the column. The CH₃CH₂- is the furthest down the column and therefore the strongest base.

Question 9

Using pKa table 3.1, page 111, which base below is needed to deprotonate the following structure? A) CH₃CH₂^- B) F^- C) NH₂^- D) OH^- E) C₆H₅O^-

Accepted Answer

Using the pKa table, refer to the conjugate base column. The strength of base increases as you go down the column. The conjugate base must be lower on the chart than the corresponding acid. The CH₃CH₂- is the only base that is strong enough to deprotonate the substrate.

Question 10

Using the periodic chart, which is the strongest bas?&#10;A) C-&#10;B) N-&#10;C) O-&#10;D) F-

Accepted Answer

On the periodic chart, basicity increases as you go up the chart in a group or as you go left across a period. Carbon is the furthest left across the 2nd period.

Question 11

Using the periodic chart, which will have the highest pKa?&#10;A) Br-&#10;B) Cl-&#10;C) F-&#10;D) I-

Accepted Answer

The answer of Using the periodic chart, which will have...

Question 12

Using the periodic chart, which is the strongest acid? A) H₂S B) HCl C) H₃P D) SiH₄

Accepted Answer

The answer of Using the periodic chart, which is the...

Question 13

Which of the following is the most acidic?  &#10;A) I&#10;B) II&#10;C) III

Accepted Answer

The answer of Which of the following is the most...

Deck 3: An Introduction to Organic Reactions and Their Mechanisms