Chapter 1

Question 1

The atomic number of boron is 5. The correct electronic configuration of boron is:
A) 1s22s3
B) 1s22p3
C) 1s22s22p1
D) 2s22p3
E) 1s22s23s1

Answer 1

C) 1s22s22p1

Question 2

How many distinct p orbitals exist in the second electron shell, where n = 2?
A) 2
B) 3
C) 4
D) 5
E) 6

Answer 2

B) 3

Question 3

The \_\_\_\_\_\_\_\_ tells us that each orbital can hold a maximum of 2 electrons.
A) aufbau principle
B) Pauli exclusion principle
C) Hund's rule principle
D) LeChatelier principle
E) uncertainty principle

Answer 3

B) Pauli exclusion principle

Question 4

A node is a region of high electron density between the two atoms in a covalent bond.
true or false?

Answer 4

Answer: FALSE

Question 5

When filling two or more orbitals of the same energy with electrons, the electrons will go into different orbitals rather than pair up in the same orbital.
true or false?

Answer 5

Answer: TRUE

Question 6

Atoms with the same number of protons but different numbers of neutrons are called ________.

Answer 6

Answer: isotopes

Question 7

The electron density of ________ orbitals has spherical symmetry.

Answer 7

s

Question 8

An oxygen atom has ________ valence electrons.

Answer 8

6

Question 9

Orbitals which are equal in energy are referred to as \_\_\_\_\_\_\_\_.
A) degenerate
B) polar
C) nodes
D) filled
E) nonpolar

Answer 9

A) degenerate

Question 10

In a carbon atom, the 2s and 2p orbitals are equal in energy.
true or false?

Answer 10

Answer: FALSE

Question 11

A carbon-hydrogen bond in ethane (CH3CH3) is best described a \_\_\_\_\_\_\_\_.
A) highly polar
B) essentially nonpolar
C) ionic
D) a multiple bond
E) resonance stabilized

Answer 11

B) essentially nonpolar

Question 12

The electronegativity of elements on the periodic table increases going \_\_\_\_\_\_\_\_ a column and to the \_\_\_\_\_\_\_\_ in each row.
A) up, right 
B) up, left
C) down, right
D) down, left

Answer 12

A) up, right

Question 13

Which of the following molecules contains a polar covalent bond?
A) H2
B) F2
C) CH3Cl
D) NaCl
E) He

Answer 13

C) CH3Cl

Question 14

The compound methylamine, CH3NH2, contains a C-N bond. In this bond, which of the following best describes the charge on the carbon atom?
A) +1
B) slightly positive
C) uncharged
D) slightly negative
E) -1

Answer 14

B) slightly positive

Question 15

The formal charge on oxygen in dimethyl ether, CH3OCH3, is \_\_\_\_\_\_\_\_.
A) +2
B) +1
C) 0
D) -1
E) -2

Answer 15

C) 0

Question 16

For most compounds in which a nitrogen atom bears no formal charge, the valence of this nitrogen atom is ________.

Answer 16

Answer: 3

Question 17

In the compound sodium methoxide (NaOCH3), there is \_\_\_\_\_\_\_\_ bonding.
A) ionic
B) polar covalent
C) nonpolar covalent
D) a mixture of ionic and covalent
E) resonance stabilized

Answer 17

D) a mixture of ionic and covalent

Question 18

Which of the following compounds are covalent compounds?
A) KCl
B) CF4
C) NH3
D) both A and B
E) both B and C

Answer 18

E) both B and C

Question 19

When a negatively charged species is most appropriately depicted as a hybrid of several resonance forms, the negative charge present is considered to be rapidly moving between the resonance forms bearing the formal negative charge.
true or false?

Answer 19

Answer: FALSE

Question 20

When a molecule can best be represented as a series of resonance forms, each of these forms always contributes to the same degree in the hybrid.
true or false?

Answer 20

Answer: FALSE

Question 21

A sample of compound X is subjected to elemental analysis and the following percentages by weight are found: 39.97% C, 6.73% H, and 53.30% O. The molecular weight of X is 90. What is the empirical formula of X?
A) C6HO8
B) C2H4O2
C) C4H10O2
D) C3H6O3
E) CH2O

Answer 21

E) CH2O

Question 22

Calculate the molecular formula for the organic compound whose quantitative elemental analysis showed 48.6% caron and 8.1% hydrogen by weight.
A) CH2O
B) C2H4O2
C) C2H6
D) C3H6O
E) C3H6O2

Answer 22

E) C3H6O2

Question 23

The pH of a 150 mL aqueous solution of 2.13 x 10-3 M HCl is \_\_\_\_\_\_\_\_.
A) -3.000
B) 3.000
C) 2.672
D) 2.130
E) none of the above

Answer 23

C) 2.672

Question 24

What is the pKa and general acid strength of formic acid if its conjugate base form has a pKb of 10.23?
A) 3.77 - fairly strong weak acid
B) 5.99 - moderately strong weak acid
C) 14.00 - not an acid but rather a strong base
D) 3.23 - fairly strong weak acid
E) cannot be determined from the information given

Answer 24

A) 3.77 - fairly strong weak acid

Question 25

The conjugate acid of ammonia, NH3, is \_\_\_\_\_\_\_\_.
A) NH2-
B) NH2OH
C) NH4+
D) none of the above

Answer 25

C) NH4+

Question 26

The Ka of formic acid is 1.7 x 10-4. The pKa of formic acid is \_\_\_\_\_\_\_\_.
A) 1.70
B) 4.00
C) -2.36
D) 3.77
E) 10.38

Answer 26

D) 3.77

Question 27

When methanol (CH3OH) acts as a base, its conjugate acid is \_\_\_\_\_\_\_\_.
A) -CH2OH
B) CH3O-
C) CH4OH
D) CH3OH2+
E) CH4O+

Answer 27

D) CH3OH2+

Question 28

Which of the following pairs of bases lists the stronger base first?
A) I-  >  Cl-
B) H2O  >  HO-
C) HO-  >  H2N-
D) CH3COO-  >  HO-
E) H2N-  >  CH3COO-

Answer 28

E) H2N- > CH3COO-

Question 29

According to the following pKa values listed for a set of acids, which would lead to the strongest conjugate base?
A) -2
B) 1
C) 7
D) 25
E) 50

Answer 29

E) 50

Question 30

Rank the following compounds in order of increasing acidity: CH3OH, HCl, NH3, and CH4.

Answer 30

Answer: CH4

Question 31

Rank the following compounds in order of increasing basicity: CH3O-, H2N-, H2O, and NH3.

Answer 31

Answer: H2O

Question 32

Which of the following acids has the most stable conjugate base?
A) CH3CO2H
B) CH3CHO
C) CH3CH2OH
D) CH3CH2SH
E) CH3SO3H

Answer 32

E) CH3SO3H

Question 33

The hydroxide ion (HO-) cannot function well as which of the following?
A) a Bronsted-Lowry base
B) a Lewis base
C) a nucleophile
D) an electron-pair acceptor
E) a proton acceptor

Answer 33

D) an electron-pair acceptor

Question 34

Which of the following terms comes closest to describing an electrophile?
A) anion
B) Lewis base
C) Lewis acid
D) nucleophile
E) nonpolar

Answer 34

C) Lewis acid

Question 35

According to the Lewis definition, which of the following may act as acids?
A) NH3
B) HCl
C) AlCl3
D) A & B
E) A, B, & C

Answer 35

E) A, B, & C

Question 36

Consider the species CH3O-, NH2-, and CH3COO-. Rank these ions in order of increasing basicity.

Answer 36

Answer: CH3COO-