Question 1

What is the mechanism and type of the reaction between ammonia and chloromethane?

  A  

electrophilic addition

  B  

nucleophilic addition

  C  

free radical substitution

  D  

nucleophilic substitution

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Question 2

The depletion of the ozone layer in the upper atmosphere reduces the Earth’s natural protection from harmful ultraviolet radiation.

Which compound would cause the most depletion of the ozone layer?

  A  

CCl3F

  B  

CF4

  C  

CHClF2

  D  

CH2F2

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Question 3

Which radical is most likely to form by the homolytic fission of one covalent bond in bromochloromethane, CH2BrCl?

  A  

•CH2Cl

  B  

•CH2Br

  C  

•CHBrCl 

  D  

•CH2BrCl

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Question 4

The formation of a carbocation from a halogenoalkane is an example of

  A  

homolytic fission

  B  

heterolytic fission

  C  

an initiation reaction

  D  

a propagation reaction

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Question 5

What describes the first step in the nucleophilic substitution reaction of ammonia with a halogenoalkane?

  A  

NH3 attacks the halogen atom

  B  

NH2- attacks the carbon atom next to the halogen

  C  

NH3 forms a bond with its lone pair to the carbon atom next to the halogen


  D  

the halogen atom is lost as a radical

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Question 6

Which statement correctly describes the boiling points of fluoroethane and iodoethane?

  A  

fluoroethane has the higher boiling point because it forms hydrogen bonds

  B  

fluoroethane has the higher boiling point because the C-F bond is stronger than C–I

  C  

iodoethane has the higher boiling point because it forms the stronger instantaneous dipole–induced dipole bonds

  D  

iodoethane has the higher boiling point because the C-I bond is less polar than C-F

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Question 7

When heated with NaOH(aq), 1-iodobutane is hydrolysed at amuch faster rate than 1-chlorobutane.

Which statement explains the different rates?

  A  

the C-I bond enthalpy is greater than the C-Cl bond enthalpy

  B  

the C-I bond is less polar than the C-Cl bond

  C  

the C-I bond has a C atom with a greater δ+ charge than in the C-Cl bond

  D  

the C-I bond requires less energy to break than the C-Cl bond

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Question 8

Which equation represents a termination step?

  A  

CH3CH2CH3 + Br• ➔ CH3CHCH3• + HBr

  B  

O3 + ClO• ➔ Cl• + 2O2

  C  

RO• + H2C=CH2 ➔ ROCH2CH2•

  D  

CH3CFCl• + Cl• ➔ CH3CFCl2

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Question 9

Why are fluoroalkanes unreactive?

  A  

fluorine is highly electronegative

  B  

the F- ion is very stable

  C  

they are polar molecules

  D  

the C-F bond is very strong

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Question 10

Which equation represents a propagation step?

  A  

•CH2Cl + Cl• ➔ CH2Cl2

  B  

•CH3 + •CH3 ➔ C2H6

  C  

Cl2 ➔ Cl• + Cl•

  D  

CH3Cl + Cl• ➔ •CH2Cl + HCl

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Question 11

Which equation represents an initiation step?

  A  

CH3CH2CHBr• + Br2 ➔ CH3CH2CHBr2 + Br•

  B  

O3 + Cl• ➔ O2 + ClO•

  C  

RCH2CH2• + H2C=CH2 ➔ RCH2CH2CH2CH2•

  D  

CH3CFCl2 ➔ CH3CFCl• + Cl•

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