Question 1

Consider the following molecule with protons labeled,I-III.Rank these protons in order of decreasing acidity,putting the most acidic first.

Accepted Answer

A) I > II > III 
B) I > III > II 
C) III > II > I 
D) III > I > II 
A) I > II > III 
B) I > III > II 
C) III > II > I 
D) III > I > II

Question 2

Which is the conjugate base in the following reaction?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 3

Which of the following concepts can be used to explain the difference in acidity between acetylene (C2H2)and ethylene (C2H4)?

Accepted Answer

A) Size 
B) Resonance 
C) Inductive effect 
D) Hybridization 
A) Size 
B) Resonance 
C) Inductive effect 
D) Hybridization

Question 4

Rank the following conjugate bases in order of increasing basicity,putting the least basic first.

Accepted Answer

A) II < I < III 
B) II < III < I 
C) I < II < III 
D) I < III < II 
A) II < I < III 
B) II < III < I 
C) I < II < III 
D) I < III < II

Question 5

Identify the Lewis acid in the following reaction.

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 6

Which of the following statements about Lewis acids is true?

Accepted Answer

A) Lewis acids are proton donors. 
B) Lewis acids are proton acceptors. 
C) Lewis acids are electron pair donors. 
D) Lewis acids are electron pair acceptors. 
A) Lewis acids are proton donors. 
B) Lewis acids are proton acceptors. 
C) Lewis acids are electron pair donors. 
D) Lewis acids are electron pair acceptors.

Question 7

Which of the following compounds has the lowest pKa?

Accepted Answer

A) H2O 
B) H2S 
C) NH3 
D) CH4 
A) H2O 
B) H2S 
C) NH3 
D) CH4

Question 8

Which of the following concepts can be used to explain the difference in acidity between acetic acid (CH3COOH)and ethanol (CH3CH2OH)?

Accepted Answer

A) Hybridization 
B) Electronegativity 
C) Resonance 
D) Size 
A) Hybridization 
B) Electronegativity 
C) Resonance 
D) Size

Question 9

Consider the following structures I-IV.Which two species represent constitutional isomers?

Accepted Answer

A) I and II 
B) I and III 
C) I and IV 
D) II and IV 
A) I and II 
B) I and III 
C) I and IV 
D) II and IV

Question 10

Which of the following statements explains why H2O is a stronger acid than CH4?

Accepted Answer

A) H2O can form hydrogen bonds while CH4 cannot. 
B) H2O forms a less stable conjugate base,HO-. 
C) CH4 forms a more stable conjugate base,CH3-. 
D) H2O forms a more stable conjugate base,HO-. 
A) H2O can form hydrogen bonds while CH4 cannot. 
B) H2O forms a less stable conjugate base,HO-. 
C) CH4 forms a more stable conjugate base,CH3-. 
D) H2O forms a more stable conjugate base,HO-.

Question 11

Which of the following species is not a Brønsted-Lowry base?

Accepted Answer

A) BF3 
B) NH3 
C) H2O 
D) PO43- 
A) BF3 
B) NH3 
C) H2O 
D) PO43-

Question 12

What is the direction of equilibrium when acetylene (C2H2)reacts with ethoxide (CH3CH2O-)in an acid-base reaction?

Accepted Answer

A) Left 
B) Right 
C) Neither 
D) Cannot be determined 
A) Left 
B) Right 
C) Neither 
D) Cannot be determined

Question 13

Which of the following compounds is the weakest acid?

Accepted Answer

A) HF 
B) HCl 
C) HBr 
D) HI 
A) HF 
B) HCl 
C) HBr 
D) HI

Question 14

Which of the following concepts can be used to explain the difference in acidity between ethanol (CH3CH2OH)and 2-fluoroethanol (FCH2CH2OH)?

Accepted Answer

A) Size 
B) Inductive effect 
C) Resonance 
D) Hybridization 
A) Size 
B) Inductive effect 
C) Resonance 
D) Hybridization

Question 15

Which of the following statements about Lewis bases is true?

Accepted Answer

A) Lewis bases are electron pair acceptors. 
B) Lewis bases are electron pair donors. 
C) Lewis bases are proton donors. 
D) Lewis bases are proton acceptors. 
A) Lewis bases are electron pair acceptors. 
B) Lewis bases are electron pair donors. 
C) Lewis bases are proton donors. 
D) Lewis bases are proton acceptors.

Question 16

Which of the following ranks the compounds in order of increasing acidity,putting the least acidic first?

Accepted Answer

A) CH4 2O 3 
B) H2O 3 4 
C) NH3 4 2O 
D) CH4 3 2O 
A) CH4 2O 3 
B) H2O 3 4 
C) NH3 4 2O 
D) CH4 3 2O

Question 17

Rank the following compounds in order of increasing acidity,putting the least acidic first.

Accepted Answer

A) I < IV < III < II 
B) I < III < IV < II 
C) II < III < IV < I 
D) II < IV < III < I 
A) I < IV < III < II 
B) I < III < IV < II 
C) II < III < IV < I 
D) II < IV < III < I

Question 18

Which is the conjugate base in the following reaction?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 19

Which of the following species is the conjugate base of the hydronium ion,H3O+?

Accepted Answer

A) H3O 
B) H2O- 
C) H2O 
D) HO- 
A) H3O 
B) H2O- 
C) H2O 
D) HO-

Question 20

Which of the following statements about acid strength is true?

Accepted Answer

A) The stronger the acid,the further the equilibrium lies to the left. 
B) The stronger the acid,the smaller the Ka. 
C) The stronger the acid,the larger the pKa. 
D) The stronger the acid,the smaller the pKa. 
A) The stronger the acid,the further the equilibrium lies to the left. 
B) The stronger the acid,the smaller the Ka. 
C) The stronger the acid,the larger the pKa. 
D) The stronger the acid,the smaller the pKa.

Exam 2: Acids and Bases

Consider the following molecule with protons labeled,I-III.Rank these protons in order of decreasing acidity,putting the most acidic first.

Which is the conjugate base in the following reaction?

Which of the following concepts can be used to explain the difference in acidity between acetylene (C2H2)and ethylene (C2H4)?

Rank the following conjugate bases in order of increasing basicity,putting the least basic first.

Identify the Lewis acid in the following reaction.

Which of the following statements about Lewis acids is true?

Which of the following compounds has the lowest pKa?

Which of the following concepts can be used to explain the difference in acidity between acetic acid (CH3COOH)and ethanol (CH3CH2OH)?

Consider the following structures I-IV.Which two species represent constitutional isomers?

Which of the following statements explains why H2O is a stronger acid than CH4?

Which of the following species is not a Brønsted-Lowry base?

What is the direction of equilibrium when acetylene (C2H2)reacts with ethoxide (CH3CH2O-)in an acid-base reaction?

Which of the following compounds is the weakest acid?

Which of the following concepts can be used to explain the difference in acidity between ethanol (CH3CH2OH)and 2-fluoroethanol (FCH2CH2OH)?

Which of the following statements about Lewis bases is true?

Which of the following ranks the compounds in order of increasing acidity,putting the least acidic first?

Rank the following compounds in order of increasing acidity,putting the least acidic first.

Which is the conjugate base in the following reaction?

Which of the following species is the conjugate base of the hydronium ion,H3O+?

Which of the following statements about acid strength is true?

Structure and Bonding

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Understanding Organic Reactions

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols,ethers,and Related Compounds

Alkenes and Addition Reactions

Alkynes and Synthesis

Oxidation and Reduction

Radical Reactions

Conjugation,resonance,and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Aldehydes and Ketones - Nucleophilic Addition

Carboxylic Acids and the Acidity of the O-H Bond

Carboxylic Acids and Their Derivatives Nucleophilic Acyl Substitution

Substitution Reactions of Carbonyl Compounds at the a Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond-Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Spectroscopy A: Mass Spectrometry

Spectroscopy B: Infrared Spectroscopy

Spectroscopy C: Nuclear Magnetic Resonance Spectroscopy

Filters

Which of the following concepts can be used to explain the difference in acidity between acetylene (C₂H₂)and ethylene (C₂H₄)?

Which of the following compounds has the lowest pK_a?

Which of the following concepts can be used to explain the difference in acidity between acetic acid (CH₃COOH)and ethanol (CH₃CH₂OH)?

Which of the following statements explains why H₂O is a stronger acid than CH₄?

What is the direction of equilibrium when acetylene (C₂H₂)reacts with ethoxide (CH₃CH₂O^-)in an acid-base reaction?

Which of the following concepts can be used to explain the difference in acidity between ethanol (CH₃CH₂OH)and 2-fluoroethanol (FCH₂CH₂OH)?

Which of the following species is the conjugate base of the hydronium ion,H₃O⁺?