Solomons Testbank1 Struktur Bindn + Svar

Chapter 1

MULTIPLE CHOICE QUESTIONS Solomons Chapter 1 (Answers on page 14)

Chapter 1

Topic: Lewis Structures, Formal Charges 5. Listed below are electron dot formulas for several simple molecules and ions. All valence electrons are shown; however, electrical charges have been omitted deliberately.

H : Be : H

H .. H:B:H .. H

H .. H:N:H ..

H .. H:N:H .. H

H .. H:O:H ..

I

II

III

IV

V

Topic: Atomic Orbitals, Molecular Orbitals Hybridization 1. When the 1s orbitals of two hydrogen atoms combine to form a hydrogen molecule, how many molecular orbitals are formed? A) 1 B) 2 C) 3 D) 4 E) 5 2. When the ls orbitals of two hydrogen atoms combine to form a hydrogen molecule, which molecular orbitals are formed? A) One bonding molecular orbital only B) Two bonding molecular orbitals C) One bonding molecular orbital and one antibonding molecular orbital D) Two antibonding molecular orbitals E) Three bonding molecular orbitals 3. The following electron configuration represents _______.

A) B) C) D) E) 4. A) B) C) D) E)

1s 2sp3 2sp3 2sp3 2sp3 the ground state of boron. the sp3 hybridized state of carbon. the sp3 hybridized state of nitrogen. the ground state of carbon. an excited state of carbon.

A) B) C) D) E)

Which of the structures actually bear(s) a positive charge? I II III III & V IV & V

6. What is the formal charge on oxygen in the following structure? .. H3C

O

CH3

CH3

A) B) C) D) E)

+2 +1 0 -1 -2

7. In which structure(s) below does the oxygen have a formal charge of +1? H

.. O

H

H

.. O: ..

1

I I only II only I and III I and IV I, III, and IV s

A) B) C) D) E)

..

C

O

H

H

Identify the atomic orbitals in the C-C sigma bond in ethyne. (2sp2, 2sp2) (2sp3, 2sp3) (2sp, 2sp) (2p, 2p) (2sp, 1s)

H

2

H3C

..

O

CH3

III

II

H

IV

CH3

Chapter 1

Chapter 1

8. Which structure(s) contain(s) an oxygen that bears a formal charge of +1? .. .. :O :O .. .. .. .. : O C O: H C H3C O H H3C O CH3 C :O : : : : O O .. .. ..: H CH3 I II III IV V A) B) C) D) E)

I and II III and IV V II I and V

D) All of these E) None of these

12. Which is NOT a correct Lewis structure? .. A) H N F : ..

9. Which of the following molecules or ions has a nitrogen with a formal charge of -1? (Charges on ions have been omitted.) .. A) : N H H

B) H

.. N

D) H3C E) H3C

N

..

C) H

.H. O ..

H

N

CH3

H C

N:

N

CH2

I

.. .O.

.. F: .. .. O H . .. . :O H B

:O .. H E) None of these

H3C

.. N ..

H

H

H

.. N

.. .OH .

H3C

..

NH2

H

A) B) C) D) E)

C

D)

CH3

13. Listed below are electron dot formulas for several simple molecules and ions. All valence electrons are shown; however, electrical charges have been omitted deliberately.

10. In which structure(s) below does nitrogen have a formal charge of +1? H3C

H

H

.. H

H H

B)

H

C) H

Topic: Lewis Structures, Formal Charges 11. Which of the following is an ion with a single negative charge? .. A) H3C O : .. .. .... B) : O N O : .. .. C) : O: .. :O N :O ..:

H3C

.. N

CH3

II

III

I II and IV III and V I and V V

IV

H .. H:B:H .. H

H .. H:N:H ..

H .. H:N:H .. H

H .. H:O:H ..

I

II

III

IV

V

V

A) B) C) D) E)

3

H : Be : H

CH3

Which of the structures is negatively charged? I II III IV V

4

Chapter 1

Chapter 1

Topic: Lewis Structures, Formal Charges

Topic: Lewis Structures, Formal Charges Molecular Geometry

14. Which compound contains a nitrogen atom with a formal positive charge?

A) B) C) D) E)

N

H N

N

I

II

III

I II III More than one of the above None of the above

15. In which of these cases does the central atom have a zero formal charge? A) HFH H B) C)

H3C O F F

B F

D) H3C

CH3

F

H N

CH3

H CH3

E) H3C

C

CH3

CH3

16. The formal charge on sulfur in sulfuric acid is: O H O

S

O H

17. Expansion of the valence shell to accommodate more than eight electrons is possible with: A) Fluorine B) Nitrogen C) Carbon D) Sulfur E) Beryllium 18. A) B) C) D) E)

Based on VSEPR theory, which of the following would have a trigonal planar shape? CH3)3N HCN NH4+ CH3! CH3+

19. A) B) C) D) E)

What shape does the methyl cation, CH3+, have? Octahedral Tetrahedral Trigonal planar Linear Trigonal pyramidal

20. A) B) C) D) E)

What bond angle is associated with a tetrahedral molecule? 120° 109.5° 180° 90° 45°

21. A) B) C) D) E)

What would be the spatial arrangement of the atoms of the methyl anion, :CH3-? Octahedral Tetrahedral Trigonal planar Linear Trigonal pyramidal

22. A) B) C) D) E)

Which of these structures would be a perfectly regular tetrahedron? CH3Br CH2Br2 CHBr3 CBr4 More than one of these

O

A) B) C) D) E)

0 -1 +1 -2 +2

5

6

Chapter 1

Topic: Periodic Properties, Electronegativity 23. A) B) C) D) E)

Chapter 1

Topic: Atomic Orbitals, Bonding

Select the most electronegative element. H O N B C

28. A) B) C) D) E)

Topic: Atomic Orbitals, Hybridization

Which of these substances contains both covalent and ionic bonds? NH4Cl H2O2 CH4 HCN H2S

Topic: Atomic Orbitals, Periodic Trends, Electronegativity 3

24. A) B) C) D) E)

In which molecule is the central atom sp hybridized? CH4 NH3 H2O All of these None of these

25. A) B) C) D) E)

Which compound has the shortest carbon-carbon bond(s)? CH3CH3 CH2=CH2 HC"CH CH3CH2CH3 All carbon-carbon bonds are the same length.

26. A) B) C) D) E)

Which of the following contains an sp2-hybridized carbon? CH4 CH3:! CH3CH3 CH3+ HC"CH

27. Which is the shortest of the carbon-carbon single bonds indicated by arrows in the following compounds? A)

29. A) B) C) D) E)

The greatest degree of ionic character is anticipated for the bond between: H and C H and Cl C and Cl H and Br Br and Cl

Topic: Atomic Orbitals, Hybridization 30. A) B) C) D)

Which molecule contains an sp-hybridized carbon? HCN CH2=CH2 CH3Cl H

C O H

E) CH3CH3 Topic: Atomic Orbitals, Lewis structures, Resonance 31. Which of the structures below is not expected to contribute to the CO2 resonance hybrid? A) O

C

O

C C

O O

H3C

CH3

B) O C) O D)

H3C

C

E)

H3C

CH

B) C)

O

CH CH2

O

C C

O O

D) HC

C

C

CH

E) H2C HC

C CH

7

8

Chapter 1

Chapter 1

Topic: Atomic Orbitals, Lewis Structures, Resonance

Topic: General 36. Credit for the first synthesis of an organic compound from an inorganic precursor is usually given to: A) Berzelius B) Arrhenius C) Kekule D) Wohler E) Lewis

:

..

C

O

H 3C

N

:

:

Topic: Isomerism 37. CH3CH2OCH2CH3 and CH3CH2CH2CH2OH are examples of what are now termed: A) Structural isomers B) Resonance structures C) Functional isomers D) Empirical isomers E) Constitutional isomers

.

C)

.. ..

and

:

O

..

C

..

O

:

:

:

B)

:

:

O

:

:

:

32. Which of the following pairs are NOT resonance structures? A) and H 3C O N O : H 3C O N O :

:

:

O

N

O

:

.. .

: H 3C

O

and

:

.. : ..

O

D) Each of these pairs represents resonance structures. E) None of these pairs represents resonance structures. Topic: Empirical and Molecular Formulas 33. A) B) C) D) E)

What is the empirical formula for cyclohexane? (Its molecular formula is C6H12.) CH CH2 C2H4 C6H6 C2H2

34. A compound consists only of carbon, hydrogen and oxygen. Elemental analysis gave: C, 70.5%, H, 13.8%. The molecular weight of the compound was found to be 103 +/- 3. What is the molecular formula for the compound? A) C6H12O B) C5H12O2 C) C3H2O4 D) C3H6O3 E) C6H14O Topic: Isomerism Br

I

A) B) C) D) E)

Br

Topic: Lewis structures, Hybridization 39. Which molecule has a non-linear structure (i.e., for which molecule are the nuclei not in a straight line)? A) O=C=O B) H–O–H C) H–Cl D) H–C"N E) H–C"C–H Topic: Isomerism 40. Which of the following structures represent compounds that are constitutional isomers of each other?

35. Which of the following is a set of constitutional isomers? Br

Topic: Hybridization 38. What is the approximate hybridization state of the oxygen molecule in ethanol, C2H5OH? A) sp B) sp2 C) sp3 D) p3 E) d2sp3

Br

II

III

I and II II and III I, II, and III II, III, and IV I, III, and IV

IV

A) B) C) D) E)

9

I I and II I and III I, II, and III I, II, III, and IV II and III

II

III

10

IV

Chapter 1

Chapter 1

Topic: Isomerism

Topic: Isomerism

41. Which compound is not an isomer of the others? OH

O O

OH

A) B) C) D) E)

I II III I II III IV All of the above are isomers of each other.

IV

44. Which of the following represent a pair of constitutional isomers? A) and B) CH3CH=CH2 and CH2=CHCH3 Br Br C) Br

H

H

and Br

H Br

D)

H Br

H

Br

and

H

H

H

A) B) C) D) E)

Br

E) More than one of these

42. Consider the following: CH3CH2CH=CHCH2CH3 I

CH3CH2CH2CH2CH=CH2 II

CH3CH=CHCH2CH2CH3 III

CH2=CHCH2CH2CH2CH3 IV

Which two structures represent the same compound? I and II II and III I and III II and IV None of these

45. A) B) C) D) E)

Cis-trans: isomerism is possible only in the case of: CH2=CBr2 CH2=CHBr BrCH=CHBr Br2C=CHBr Br2C=CBr2

Topic: Atomic Orbitals, Hybridization, Bonding 46. Identify the atomic orbitals involved in the C-2---C-3 sigma bond (indicated by an arrow) in the following molecule: 1 4

43. Consider the following:

2

6

CH3CH2CH2CH=CHCH2CH2CH3 I

A) B) C) D) E)

CH3CH2CH2CH2CH2CH2CH=CH2 II

CH3CH2CH=CHCH2CH2CH2CH3 CH2=CHCH2CH2CH2CH2CH2CH3 III IV Which structures can exist as cis-trAns: isomers? I and II I and III I and IV II and III I alone

11

7

A) B) C) D) E)

sp2, sp2 sp2, sp sp2, sp3 sp3, sp2 sp, sp2

5

3

Topic: Molecular Geometry 47. Based on the VSEPR theory, which of the following would have a tetrahedral arrangement of electrons around the central atom? A) BH3 B) NO2 ! C) SiH4 D) CO3 2! E) SO3

12

Chapter 1

Chapter 1

Topic: Periodic Trends, Electronegativity 48. A) B) C) D) E)

Solomons Chapter 1

Select the least electronegative element P N Mg Si K

Topic: Atomic Orbitals, Hybridization 49. In which molecule(s) can the molecular geometry be attributed to an sp2 hybridized central atom? A) PBr3 B) CH4 C) CHCl3 D) HNO2 E) None of the above has an sp2 hybridized central atom Topic: Bonding, Atomic Orbitals, Hybridization 50. Which molecule has the shortest carbon-carbon single bond?

I

A) B) C) D) E)

I II III IV V

II

III

IV

V

13

Fråga 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

Svar B C C C E B E B A A D A B D E A D E C B E D B D C D D A B A D C B E E D E C B C A D B E C E C E D E

Rätt/Fel

14

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