Question 1

Which of the following bonds is least polar?

Accepted Answer

A) HF1F1F1S1F1F1F10O 
B) HF1F1F1S1F1F1F10N 
C) HF1F1F1S1F1F1F10B 
D) HF1F1F1S1F1F1F10C 
E) HF1F1F1S1F1F1F10F 
A) HF1F1F1S1F1F1F10O 
B) HF1F1F1S1F1F1F10N 
C) HF1F1F1S1F1F1F10B 
D) HF1F1F1S1F1F1F10C 
E) HF1F1F1S1F1F1F10F

Question 2

Which of the following elements contains the largest number of valence electrons?

Accepted Answer

A) P 
B) Sr 
C) C 
D) B 
E) F 
A) P 
B) Sr 
C) C 
D) B 
E) F

Question 3

One of the resonance structures of the oxalate ion (C2O42F1F1F1S1F1F1F10) is shown below. How many other resonance structures, that obey the octet rule, exist for the molecule?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3 
E) 4 
A) 0 
B) 1 
C) 2 
D) 3 
E) 4

Question 4

Rank the following species in order of increasing carbon-oxygen bond energy: CO, CO2, CO32F1F1F1S1F1F1F10.

Accepted Answer

From largest to smal

Question 5

Describe the position of electrons around one N atom in the Lewis structure of N2.

Accepted Answer

A) 3 shared electron pairs, 1 lone pair 
B) 2 shared electron pairs, 2 lone pairs 
C) 1 shared electron pair, 3 lone pairs 
D) 3 shared electron pairs 
E) 2 shared electron pairs, 1 lone pair 
A) 3 shared electron pairs, 1 lone pair 
B) 2 shared electron pairs, 2 lone pairs 
C) 1 shared electron pair, 3 lone pairs 
D) 3 shared electron pairs 
E) 2 shared electron pairs, 1 lone pair

Question 6

Which statement A-D regarding electronegativity is not correct?

Accepted Answer

A) Electronegativity is a measure of an atom's ability to attract electrons in a molecule. 
B) If the electronegativity difference is sufficiently large, then an ionic bond is formed. 
C) All bonds are polar except those between the same atoms (e.g., CO vs.O2). 
D) Pauling assigned electronegativity values to atoms based on their ionization energies and electron affinities. 
E) Statements A-D are all correct. 
A) Electronegativity is a measure of an atom's ability to attract electrons in a molecule. 
B) If the electronegativity difference is sufficiently large, then an ionic bond is formed. 
C) All bonds are polar except those between the same atoms (e.g., CO vs.O2). 
D) Pauling assigned electronegativity values to atoms based on their ionization energies and electron affinities. 
E) Statements A-D are all correct.

Question 7

Do you expect the nitrogen-oxygen bond length in the nitrate anion (NO3F1F1F1S1F1F1F10) to be the same as in the nitrite anion (NO2F1F1F1S1F1F1F10)? Explain why or why not.

Accepted Answer

In examining the Lewis structures to ide

Question 8

What is the formal charge of the carbon atom in the Lewis structure for carbonyl sulfide (OCS)?

Accepted Answer

A) 0 
B) (F1F1F1S1F1F1F102) 
C) 1 
D) 4 
E) 2 
A) 0 
B) (F1F1F1S1F1F1F102) 
C) 1 
D) 4 
E) 2

Question 9

In which one of the following molecules does the central atom have an expanded octet?

Accepted Answer

A) SF4 
B) N2O 
C) PBr3 
D) BeF2 
E) AsF3 
A) SF4 
B) N2O 
C) PBr3 
D) BeF2 
E) AsF3

Question 10

How many valence electrons does aluminum have?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 11 
E) 13 
A) 1 
B) 2 
C) 3 
D) 11 
E) 13

Question 11

Carbon dioxide is a greenhouse gas. Which of the following is the correct Lewis structure for carbon dioxide?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 12

Indicate the element with the smallest electronegativity.

Accepted Answer

A) Cl 
B) F 
C) Be 
D) K 
E) C 
A) Cl 
B) F 
C) Be 
D) K 
E) C

Question 13

Draw three resonance structures for the cyanate ion (NCOF1F1F1S1F1F1F10) that obey the octet rule. Identify the most stable form by using the concept of formal charges. Explain the reason for your choice.

Accepted Answer

@#IMG-DLM& Using the criterion of formal charge, t

Question 14

Which of the following contains an odd number of valence electrons? BrO3F1F1F1S1F1F1F10  HO2F1F1F1S1F1F1F10  N2O NO2
I II III IV

Accepted Answer

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

Question 15

Which of the following has 13 valence electrons?

Accepted Answer

A) SHF1F1F1S1F1F1F10 
B) IO 
C) NO 
D) ICl 
E) Cl2 
A) SHF1F1F1S1F1F1F10 
B) IO 
C) NO 
D) ICl 
E) Cl2

Question 16

Which of the following species contains a double bond?

Accepted Answer

A) NOF1F1F1S1F1F1F10 
B) F2 
C) CH 
D) OHF1F1F1S1F1F1F10 
E) Br2 
A) NOF1F1F1S1F1F1F10 
B) F2 
C) CH 
D) OHF1F1F1S1F1F1F10 
E) Br2

Question 17

Which of the following molecular ions has 3 valence electrons?

Accepted Answer

A) H2F1F1F1S1F1F1F10 
B) He2F1F1F1S1F1F1F10 
C) C2F1F1F1S1F1F1F10 
D) B2F1F1F1S1F1F1F10 
E) O2F1F1F1S1F1F1F10 
A) H2F1F1F1S1F1F1F10 
B) He2F1F1F1S1F1F1F10 
C) C2F1F1F1S1F1F1F10 
D) B2F1F1F1S1F1F1F10 
E) O2F1F1F1S1F1F1F10

Question 18

Indicate the ion that does not have 8 valence electrons.

Accepted Answer

A) OF1F1F1S1F1F1F10 
B) NaF1F1F1S1F1F1F10 
C) Al3F1F1F1S1F1F1F10 
D) P3F1F1F1S1F1F1F10 
E) Ar 
A) OF1F1F1S1F1F1F10 
B) NaF1F1F1S1F1F1F10 
C) Al3F1F1F1S1F1F1F10 
D) P3F1F1F1S1F1F1F10 
E) Ar

Question 19

Which statement A-D about chemical bonds is not correct?

Accepted Answer

A) Atoms combine to form molecules because the energy of the molecule is lower than the energy of the free atoms. 
B) The electrostatic potential energy explains why atoms bond together. 
C) The electrostatic potential energy is directly proportional to the charges on two particles. 
D) The electrostatic potential energy is inversely proportional to the distance between two charged particles. 
E) Statements A-D are all correct. 
A) Atoms combine to form molecules because the energy of the molecule is lower than the energy of the free atoms. 
B) The electrostatic potential energy explains why atoms bond together. 
C) The electrostatic potential energy is directly proportional to the charges on two particles. 
D) The electrostatic potential energy is inversely proportional to the distance between two charged particles. 
E) Statements A-D are all correct.

Question 20

Which sequence does not have the elements arranged correctly in order of increasing electronegativity?

Accepted Answer

A) I   F1F1F1S1F1F1F10Br   F1F1F1S1F1F1F10Cl 
B) B   F1F1F1S1F1F1F10N   F1F1F1S1F1F1F10O 
C) H   F1F1F1S1F1F1F10C   F1F1F1S1F1F1F10N 
D) H   F1F1F1S1F1F1F10Li   F1F1F1S1F1F1F10S 
E) Al   F1F1F1S1F1F1F10S   F1F1F1S1F1F1F10Cl 
A) I   F1F1F1S1F1F1F10Br   F1F1F1S1F1F1F10Cl 
B) B   F1F1F1S1F1F1F10N   F1F1F1S1F1F1F10O 
C) H   F1F1F1S1F1F1F10C   F1F1F1S1F1F1F10N 
D) H   F1F1F1S1F1F1F10Li   F1F1F1S1F1F1F10S 
E) Al   F1F1F1S1F1F1F10S   F1F1F1S1F1F1F10Cl

Exam 8: Chemical Bonds: What Makes a Gas a Greenhouse Gas

Which of the following bonds is least polar?

Which of the following elements contains the largest number of valence electrons?

One of the resonance structures of the oxalate ion (C2O42) is shown below. How many other resonance structures, that obey the octet rule, exist for the molecule?

Rank the following species in order of increasing carbon-oxygen bond energy: CO, CO2, CO32.

Describe the position of electrons around one N atom in the Lewis structure of N2.

Which statement A-D regarding electronegativity is not correct?

Do you expect the nitrogen-oxygen bond length in the nitrate anion (NO3) to be the same as in the nitrite anion (NO2)? Explain why or why not.

What is the formal charge of the carbon atom in the Lewis structure for carbonyl sulfide (OCS)?

In which one of the following molecules does the central atom have an expanded octet?

How many valence electrons does aluminum have?

Carbon dioxide is a greenhouse gas. Which of the following is the correct Lewis structure for carbon dioxide?

Indicate the element with the smallest electronegativity.

Draw three resonance structures for the cyanate ion (NCO) that obey the octet rule. Identify the most stable form by using the concept of formal charges. Explain the reason for your choice.

Which of the following contains an odd number of valence electrons? BrO3 HO2 N2O NO2 I II III IV

Which of the following has 13 valence electrons?

Which of the following species contains a double bond?

Which of the following molecular ions has 3 valence electrons?

Indicate the ion that does not have 8 valence electrons.

Which statement A-D about chemical bonds is not correct?

Which sequence does not have the elements arranged correctly in order of increasing electronegativity?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: The Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solutions: Properties and Behavior

Solids: Crystals, Alloys, and Polymers

Chemical Kinetics: Reactions in the Atmosphere

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acidbase Equilibria: Proton Transfer in Biological Systems

Additional Aqueous Equilibria: Chemistry and the Oceans

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Electrochemistry: The Quest for Clean Energy

Nuclear Chemistry: Applications to Energy and Medicine

Organic and Biological Molecules: the Compounds of Life

The Main Group Elements: Life and the Periodic Table

Transition Metals: Biological and Medical Applications

Filters

One of the resonance structures of the oxalate ion (C₂O₄²^) is shown below. How many other resonance structures, that obey the octet rule, exist for the molecule?

Rank the following species in order of increasing carbon-oxygen bond energy: CO, CO₂, CO₃²^.

Describe the position of electrons around one N atom in the Lewis structure of N₂.

Do you expect the nitrogen-oxygen bond length in the nitrate anion (NO₃^) to be the same as in the nitrite anion (NO₂^)? Explain why or why not.

Draw three resonance structures for the cyanate ion (NCO^) that obey the octet rule. Identify the most stable form by using the concept of formal charges. Explain the reason for your choice.

Which of the following contains an odd number of valence electrons? BrO₃^ HO₂^ N₂O NO₂ I II III IV