CHM 2046C Kotz 6th Edition Chapter 11
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       Question 1 of 25

 

 

The correct answer is:
carbon forms strong bonds with both itself and hydrogen.

Explanation:
Carbon is a relatively small atom that has an electronegativity value similar to hydrogen. The C-C bond energy is roughly of the same magnitude as the energies of the bonds that carbon forms to other elements.

Solution Reference:
Page 480, The Uniqueness of Carbon

1. The existence of thousands of different hydrocarbons is because

a.

carbon exists in allotropic forms.

b.

carbon can form four bonds.

c.

carbon forms strong bonds with both itself and hydrogen.

d.

carbon forms strong bonds with itself and weak bonds with hydrogen.

e.

carbon forms weak bonds with itself and strong bonds with hydrogen.



       Question 2 of 25

 

 

The correct answer is:
C8H10

Explanation:
Each intersection in the hexagon represents a carbon that has 4 bonds. At 4 of the intersections, the carbon is bonded to hydrogen.


Solution Reference:
Page 497, Aromatic Compounds

 

2. The chemical structure

represents a molecule of molecular formula:

a.

C8H10

b.

C6H6

c.

C6H8

d.

C8H12

e.

C8H6



       Question 3 of 25

 

 

The correct answer is:
percentage composition.

Explanation:
Both compounds have the same molecular formula, C5H12.

Solution Reference:
Page 487, Alkanes

3. The compounds pentane and 2-methyl butane would be expected to have the same

a.

melting points.

b.

boiling points.

c.

solubility in benzene.

d.

structural formulas.

e.

percentage composition.



       Question 4 of 25

 

 

The correct answer is:


Explanation:
Noncyclic saturated hydrocarbons have the general formula CnH2n+2. Cyclic saturated hydrocarbons have the general formula CnH2n so compound (e) cannot be an isomer.

Solution Reference:
Page 487, Alkanes

4. Four of the following compounds are structural isomers. Which one is not one of these isomers?

a.

b.

c.

d.

e.



 

 

 

 

 

       Question 5 of 25

 

 

The correct answer is:
3.

Explanation:
A student can remember the answer, but it is best to be able to draw each of the isomers without having any duplicate structures.

Solution Reference:
Page 487, Alkanes

 

5. The total number of isomeric alkanes of the molecular formula C5H12 is

a.

1.

b.

2.

c.

3.

d.

4.

e.

5.

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       Question 6 of 25

 

 

The correct answer is:
C3H6

Explanation:
CnH2n

Solution Reference:
493, Alkenes and Alkynes

6. Which one of the following is the formula of an alkene?

a.

C2H6

b.

C2H2

c.

C3H6

d.

C4H10

e.

C5H12



 

 

 

       Question 7 of 25

 

 

The correct answer is:
C3H4

Explanation:
CnH2n-2

Solution Reference:
Page 493, Alkenes and Alkynes

7. Which one of the following could be the formula of an alkyne?

a.

C4H10

b.

C3H4

c.

C6H6

d.

C6H12

e.

C3H8



       Question 8 of 25

 

 

The correct answer is:
C4H8.

Explanation:
CnH2n



Solution Reference:
Page 490, Cycloalkanes

8. The formula of cyclobutane is

a.

C4H6.

b.

C4H8.

c.

C3H6.

d.

C4H10.

e.

C4H12.



 

 

 

 

 

       Question 9 of 25

 

 

The correct answer is:
6

Explanation:
Each carbon atom needs four bonds.

Solution Reference:
Page 486, Hydrocarbons

9. How many hydrogen atoms are needed to complete the following hydrocarbon structure?

a.

4

b.

5

c.

6

d.

8

e.

10



       Question 10 of 25

 

 

The correct answer is:
alkyne.

Solution Reference:
Page 493, Alkenes and Alkynes

 

10. The hydrocarbon containing a carbon-carbon triple bond is called a(n)

a.

alkene.

b.

alkane.

c.

cycloalkene.

d.

alkyne.

e.

aromatic.

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       Question 11 of 25

 

 

The correct answer is:


Explanation:
Meta dichlorobenzene (1,3 disubstituted)
Para dichlorobenzene (1,4 disubstituted)
Ortho dichlorobenzene (1,2 disubstituted)

Solution Reference:
Page 497, Aromatic Compounds

11. The correct structure of meta dichlorobenzene is

a.

b.

c.

d.

e.



       Question 12 of 25

 

 

The correct answer is:
4

Explanation:


Solution Reference:
Page 493, Alkenes and Alkynes

12. How many different alkenes (be sure to include geometrical isomers) are there that have the formula C4H8?

a.

2

b.

3

c.

4

d.

5

e.

6



       Question 13 of 25

 

 

The correct answer is:
three double bonds.

Explanation:
There is delocalization of the bonding electrons, so effectively the carbon-carbon bonds are 1.5 bonds.

Solution Reference:
Page 497, Aromatic Compounds

13. All of the following describe benzene EXCEPT

a.

an aromatic hydrocarbon.

b.

three double bonds.

c.

resonance hybrid structures.

d.

undergoes substitution reactions.

e.

can have ortho-, meta-, and para-disubstituted products.



       Question 14 of 25

 

 

The correct answer is:
CH3HC=CHCH3

Explanation:
2-Butene can form cis and trans isomers; the other compounds listed cannot.

Solution Reference:
Page 493, Alkenes and Alkynes

14. Which of the following compounds has cis-trans isomers?


a.

H2C=C(CH3)2


b.

ClHC=C(CH3)2


c.

CH3CCH


d.

H3C-C(CH3)3


e.

CH3HC=CHCH3



       Question 15 of 25

 

 

The correct answer is:
2, 3, and 4 only

Explanation:
Compound 1 is nonsense, as there are too many hydrogen atoms and/or bonds around the central carbon atoms. 2-Butyne is CH3CCCH3 (C4H6). All the structural isomers have the formula C4H6, including compound 4.

Solution Reference:
Page 493, Alkenes and Alkynes

15. The formula(s) of a structural (functional) isomer of 2-butyne is (are)

1. CH3CHCHCH3
2. CH2=C=CHCH3
3. CH2=CHCH =CH2
4.

a.

1 only

b.

2 only

c.

2 and 3 only

d.

1, 2, and 3 only

e.

2, 3, and 4 only

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       Question 16 of 25

 

 

The correct answer is:
3.

Explanation:


Solution Reference:
Page 502, Alcohols and Amines

16. The total number of isomers with the formula C3H8O is

a.

1.

b.

2.

c.

3.

d.

4.

e.

5.



       Question 17 of 25

 

 

The correct answer is:
acids.

Solution Reference:
Page 512, Carboxylic Acids

17. The functional group

is characteristic of organic

a.

ketones.

b.

acids.

c.

aldehydes.

d.

esters.

e.

alcohols.



       Question 18 of 25

 

 

The correct answer is:


Solution Reference:
Page 514, Esters

18. Which of the following compounds is an ester?

a.

b.

c.

d.

e.



       Question 19 of 25

 

 

The correct answer is:
2.5

Explanation:
2CH3CHO + 5O2 --> 4CO2 + 4H2O

Solution Reference:
Page 511, Aldehydes and Ketones

19. The products of the complete combustion of acetaldehyde with oxygen are shown in the equation below:

___ CH3CHO + ___ O2 --> ___ CO2 + ___ H2O

When properly balanced, the equation indicates that _______ mole(s) of O2 are required for each mole of acetaldehyde.

a.

1

b.

2

c.

2.5

d.

3

e.

5



       Question 20 of 25

 

 

The correct answer is:
an organic acid and an alcohol.

Explanation:
For example:


Solution Reference:
Page 514, Esters

 

20. The reagents for the preparation of an ester could be

a.

an organic acid.

b.

an alcohol and a ketone.

c.

an ether and an alcohol.

d.

an organic acid and an alcohol.

e.

an alkene and an ether.

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       Question 21 of 25

 

 

The correct answer is:
CH3CHO.

Explanation:


Solution Reference:
Page 511, Aldehydes and Ketones

21. Ethanol can be oxidized stepwise to two stable intermediate products. One of these intermediate products is

a.

CH3CH2OOH.

b.

CO2.

c.

CH3CHO.

d.

CH3CH2OH.

e.

CH3OCH3.



       Question 22 of 25

 

 

The correct answer is:
ethers.

Solution Reference:
Page 507, Ethers

 

22. The C=O linkage occurs in all the following functional groups EXCEPT

a.

aldehydes.

b.

ketones.

c.

ethers.

d.

esters.

e.

amides.



       Question 23 of 25

 

 

The correct answer is:
C6H6 + Br2/FeBr3

Explanation:
Reactions with benzene involve an electrophilic substitution mechanism.

Solution Reference:
Page 497, Aromatic Compounds

23. Between which one of the following pairs of reagents is the reaction an electrophilic substitution reaction?

a.

CH3CH=CHCH3 + HBr

b.

CH3CH=CHCH3 + Br2

c.

CH3CH2CH2Br + NaOH(aq)

d.

C6H6 + Br2/FeBr3

e.

C2H5OH + HCl



       Question 24 of 25

 

 

The correct answer is:
Styrene

Solution Reference:
Page 520, Addition Polymers

24. Which of the following is an example of an addition polymer?

a.

Styrene

b.

Nylon

c.

Ethers

d.

Polyesters

e.

Polyamides



       Question 25 of 25

 

 

The correct answer is:
1, 2, and 3

Solution Reference:
Page 519, Synthetic Organic Polymers

25. Which of the following statements about polymers is (are) TRUE?

1. They are macromolecules.
2. They have simple repeating units.
3. Their structures can be represented by a simple repeating unit.

a.

1 only

b.

2 only

c.

3 only

d.

2 and 3 only

e.

1, 2, and 3

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