Question 1

How many "dots" should be shown in the Lewis symbol for phosphorus?

Accepted Answer

A) 1 
B) 3 
C) 5 
D) 8 
E) 10 
A) 1 
B) 3 
C) 5 
D) 8 
E) 10 C

Question 2

Which of the following would be properly classified as a set of covalent molecules?

Accepted Answer

A) NaClO4,C4H10,NH3  
B) NaCl,CH4,S8  
C) CO2,HCN,O2  
D) CO2,NH4Cl,C2H6  
E) AgCl,ScF3,P4  
A) NaClO4,C4H10,NH3  
B) NaCl,CH4,S8  
C) CO2,HCN,O2  
D) CO2,NH4Cl,C2H6  
E) AgCl,ScF3,P4  C

Question 3

Given the following bond lengths in pm:
N-N,145;N =N,123;Br-Br,228
What is the best estimate of the N-Br bond length in NBr3 in pm?

Accepted Answer

A) 373 pm 
B) 125 pm 
C) 351 pm 
D) 216 pm 
E) 561 pm 
A) 373 pm 
B) 125 pm 
C) 351 pm 
D) 216 pm 
E) 561 pm D

Question 4

Given the bond enthalpies C-O (360),C =O (707),O =O (498),H-O (464),C-H (414),all in kJ/mol,estimate ΔH° for the following reaction: 
CH3OCH3(g)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(g).

Accepted Answer

A) -2332 kJ/mol 
B) -242 kJ/mol 
C) 870 kJ/mol 
D) -2106 kJ/mol 
E) -914 kJ/mol 
A) -2332 kJ/mol 
B) -242 kJ/mol 
C) 870 kJ/mol 
D) -2106 kJ/mol 
E) -914 kJ/mol

Question 5

Choose the INCORRECT statement.

Accepted Answer

A) The geometrical distribution of electron groups is the electron-group geometry. 
B) The geometrical arrangement of the atomic nuclei is the molecular geometry. 
C) A polar molecule has a dipole moment. 
D) A dipole moment is the product of the number of atoms and the charge. 
E) A nonpolar molecule can have polar bonds. 
A) The geometrical distribution of electron groups is the electron-group geometry. 
B) The geometrical arrangement of the atomic nuclei is the molecular geometry. 
C) A polar molecule has a dipole moment. 
D) A dipole moment is the product of the number of atoms and the charge. 
E) A nonpolar molecule can have polar bonds.

Question 6

Of the following elements,which has the lowest electronegativity?

Accepted Answer

A) Sr 
B) I 
C) Ba 
D) At 
A) Sr 
B) I 
C) Ba 
D) At

Question 7

Given the bond enthalpies N   N (946),H-H (436),H-N (389),all in kJ/mol,estimate ΔH° for the following reaction: 
N2(g)+ 3 H2(g)→ 2NH3(g).

Accepted Answer

A) -215 kJ/mol 
B) -863 kJ/mol 
C) -80 kJ/mol 
D) 568 kJ/mol 
E) -1476 kJ/mol 
A) -215 kJ/mol 
B) -863 kJ/mol 
C) -80 kJ/mol 
D) 568 kJ/mol 
E) -1476 kJ/mol

Question 8

Bonds between identical atoms are nonpolar bonds.

Accepted Answer

A) True 
 B)False

Question 9

After drawing the Lewis dot structure of HCOOH,pick the INCORRECT statement from the following.

Accepted Answer

A) The oxygen not bonded to hydrogen has a double bond to carbon. 
B) The carbon has a lone pair. 
C) Both oxygens have two lone pairs. 
D) The O-H bond is a single bond. 
E) The C-H bond is a single bond. 
A) The oxygen not bonded to hydrogen has a double bond to carbon. 
B) The carbon has a lone pair. 
C) Both oxygens have two lone pairs. 
D) The O-H bond is a single bond. 
E) The C-H bond is a single bond.

Question 10

Arrange the following in order of increasing electronegativity: 
Cs,F,As,Cl.

Accepted Answer

A) As < Cl < Cs < F 
B) Cl < As < F < Cs 
C) As < F < Cs < Cl 
D) Cl < Cs < F < As 
E) Cs < As < Cl < F 
A) As < Cl < Cs < F 
B) Cl < As < F < Cs 
C) As < F < Cs < Cl 
D) Cl < Cs < F < As 
E) Cs < As < Cl < F

Question 11

Which of the following species is best represented by a resonance hybrid having two contributing structures?

Accepted Answer

A) nitric acid 
B) nitrous acid 
C) nitride ion 
D) nitrate ion 
E) nitrogen 
A) nitric acid 
B) nitrous acid 
C) nitride ion 
D) nitrate ion 
E) nitrogen

Question 12

Which of the following must be paramagnetic?

Accepted Answer

A) F2  
B) N2  
C) SO2+  
D) H2  
E) ClO2-  
A) F2  
B) N2  
C) SO2+  
D) H2  
E) ClO2-

Question 13

After drawing the Lewis dot structure for CO2,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Accepted Answer

A) single bond(s)= 2,double bond(s)= 2,lone pair(s)= 0 
B) single bond(s)= 2,double bond(s)= 0,lone pair(s)= 2 
C) single bond(s)= 0,double bond(s)= 2,lone pair(s)= 0 
D) single bond(s)= 2,double bond(s)= 0,lone pair(s)= 1 
E) single bond(s)= 0,double bond(s)= 2,lone pair(s)= 2 
A) single bond(s)= 2,double bond(s)= 2,lone pair(s)= 0 
B) single bond(s)= 2,double bond(s)= 0,lone pair(s)= 2 
C) single bond(s)= 0,double bond(s)= 2,lone pair(s)= 0 
D) single bond(s)= 2,double bond(s)= 0,lone pair(s)= 1 
E) single bond(s)= 0,double bond(s)= 2,lone pair(s)= 2

Question 14

Given the bond enthalpies C-C (348),C=O (707),O =O (498),H-O (464),C-H (414)all in kJ/mol,compute ΔH° in kJ/mol for the complete combustion of C7H16.

Accepted Answer

A) -3.13 × 103 kJ/mol 
B) -2.93 × 103 kJ/mol 
C) -2.57 × 103 kJ/mol 
D) -2.43 × 103 kJ/mol 
E) +2.57 × 103 kJ/mol 
A) -3.13 × 103 kJ/mol 
B) -2.93 × 103 kJ/mol 
C) -2.57 × 103 kJ/mol 
D) -2.43 × 103 kJ/mol 
E) +2.57 × 103 kJ/mol

Question 15

Which of the following has a molecular structure that can be represented without use of an "expanded octet"?

Accepted Answer

A) Fe(CN)63-  
B) C2Cl6  
C) SF6  
D) PF5  
E) PtCl5-  
A) Fe(CN)63-  
B) C2Cl6  
C) SF6  
D) PF5  
E) PtCl5-

Question 16

After drawing the Lewis dot structure for CH2O,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Accepted Answer

A) single bond(s)= 1,double bond(s)= 2,lone pair(s)= 0 
B) single bond(s)= 2,double bond(s)= 1,lone pair(s)= 1 
C) single bond(s)= 3,double bond(s)= 0,lone pair(s)= 1 
D) single bond(s)= 3,double bond(s)= 1,lone pair(s)= 0 
E) single bond(s)= 2,double bond(s)= 1,lone pair(s)= 0 
A) single bond(s)= 1,double bond(s)= 2,lone pair(s)= 0 
B) single bond(s)= 2,double bond(s)= 1,lone pair(s)= 1 
C) single bond(s)= 3,double bond(s)= 0,lone pair(s)= 1 
D) single bond(s)= 3,double bond(s)= 1,lone pair(s)= 0 
E) single bond(s)= 2,double bond(s)= 1,lone pair(s)= 0

Question 17

Which of the following species exhibits resonance?

Accepted Answer

A) OFS1U1P12 S1S1P0 
B) ClOS1U1B13S1U1B0S1U1P1-S1S1P0 
C) NS1U1B12S1U1B0 
D) PClS1U1B15 S1U1B0 
E) BrFS1U1B13S1U1B0 
A) OFS1U1P12 S1S1P0 
B) ClOS1U1B13S1U1B0S1U1P1-S1S1P0 
C) NS1U1B12S1U1B0 
D) PClS1U1B15 S1U1B0 
E) BrFS1U1B13S1U1B0

Question 18

After drawing the Lewis dot structure for CH3Cl,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Accepted Answer

A) single bond(s)= 4,double bond(s)= 1,lone pair(s)= 0 
B) single bond(s)= 4,double bond(s)= 0,lone pair(s)= 1 
C) single bond(s)= 3,double bond(s)= 0,lone pair(s)= 1 
D) single bond(s)= 4,double bond(s)= 0,lone pair(s)= 0 
E) single bond(s)= 3,double bond(s)= 1,lone pair(s)= 0 
A) single bond(s)= 4,double bond(s)= 1,lone pair(s)= 0 
B) single bond(s)= 4,double bond(s)= 0,lone pair(s)= 1 
C) single bond(s)= 3,double bond(s)= 0,lone pair(s)= 1 
D) single bond(s)= 4,double bond(s)= 0,lone pair(s)= 0 
E) single bond(s)= 3,double bond(s)= 1,lone pair(s)= 0

Question 19

Given the following bond lengths in pm:
C-C,154;C =C,134;Cl-Cl,199
What is the best estimate of the C-Cl bond length in CCl4 in pm?

Accepted Answer

A) 353 pm 
B) 706 pm 
C) 167 pm 
D) 333 pm 
E) 177 pm 
A) 353 pm 
B) 706 pm 
C) 167 pm 
D) 333 pm 
E) 177 pm

Question 20

Which compound would be expected to have the shortest carbon-carbon bond?

Accepted Answer

A) H3CCH3  
B) HCCH 
C) H2CCH2  
D) F3CCF3  
E) Cl2CCCl2  
A) H3CCH3  
B) HCCH 
C) H2CCH2  
D) F3CCF3  
E) Cl2CCCl2

Exam 10: Chemical Bonding I: Basic Concepts

How many "dots" should be shown in the Lewis symbol for phosphorus?

Which of the following would be properly classified as a set of covalent molecules?

Given the following bond lengths in pm: N-N,145;N =N,123;Br-Br,228 What is the best estimate of the N-Br bond length in NBr3 in pm?

Given the bond enthalpies C-O (360),C =O (707),O =O (498),H-O (464),C-H (414),all in kJ/mol,estimate ΔH° for the following reaction: CH3OCH3(g)+ 3 O2(g)→ 2 CO2(g)+ 3 H2O(g).

Choose the INCORRECT statement.

Of the following elements,which has the lowest electronegativity?

Given the bond enthalpies N N (946),H-H (436),H-N (389),all in kJ/mol,estimate ΔH° for the following reaction: N2(g)+ 3 H2(g)→ 2NH3(g).

Bonds between identical atoms are nonpolar bonds.

After drawing the Lewis dot structure of HCOOH,pick the INCORRECT statement from the following.

Arrange the following in order of increasing electronegativity: Cs,F,As,Cl.

Which of the following species is best represented by a resonance hybrid having two contributing structures?

Which of the following must be paramagnetic?

After drawing the Lewis dot structure for CO2,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Given the bond enthalpies C-C (348),C=O (707),O =O (498),H-O (464),C-H (414)all in kJ/mol,compute ΔH° in kJ/mol for the complete combustion of C7H16.

Which of the following has a molecular structure that can be represented without use of an "expanded octet"?

After drawing the Lewis dot structure for CH2O,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Which of the following species exhibits resonance?

After drawing the Lewis dot structure for CH3Cl,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Given the following bond lengths in pm: C-C,154;C =C,134;Cl-Cl,199 What is the best estimate of the C-Cl bond length in CCl4 in pm?

Which compound would be expected to have the shortest carbon-carbon bond?

Matter: Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding Ii: Valence Bond and Molecular Orbital Theories

Intermolecular Forces: Liquids and Solids

Spontaneous Change: Entropy and Gibbs Energy

Solutions and Their Physical Properties

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acidbase Equilibria

Solubility and Complex-Ion Equilibria

Electrochemistry

Chemical Kinetics

Chemistry of the Main-Group Elements I: Groups 1,2,13,and 14

Chemistry of the Main-Group Elements Ii: Groups 18,17,16,15,and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

Given the following bond lengths in pm: N-N,145;N =N,123;Br-Br,228 What is the best estimate of the N-Br bond length in NBr₃ in pm?

Given the bond enthalpies C-O (360),C =O (707),O =O (498),H-O (464),C-H (414),all in kJ/mol,estimate ΔH° for the following reaction: CH₃OCH₃(g)+ 3 O₂(g)→ 2 CO₂(g)+ 3 H₂O(g).

Given the bond enthalpies N N (946),H-H (436),H-N (389),all in kJ/mol,estimate ΔH° for the following reaction: N₂(g)+ 3 H₂(g)→ 2NH₃(g).

After drawing the Lewis dot structure for CO_2,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Given the bond enthalpies C-C (348),C=O (707),O =O (498),H-O (464),C-H (414)all in kJ/mol,compute ΔH° in kJ/mol for the complete combustion of C₇H₁₆.

After drawing the Lewis dot structure for CH₂O_,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

After drawing the Lewis dot structure for CH₃Cl_,determine the number of single bond(s),double bond(s),and lone pair(s)on the central atom.

Given the following bond lengths in pm: C-C,154;C =C,134;Cl-Cl,199 What is the best estimate of the C-Cl bond length in CCl₄ in pm?