Which reaction is an example of nucleophilic substitution?
CH3CH2Br → CH2=CH2 + HBr
CH2=CH2 + HBr → CH3CH2Br
C3H7Br + NH3 → C3H7NH2 + HBr
C2H6 + Br2 → C2H5Br + HBr
Did this page help you?
Which reaction is an example of nucleophilic substitution?
CH3CH2Br → CH2=CH2 + HBr
CH2=CH2 + HBr → CH3CH2Br
C3H7Br + NH3 → C3H7NH2 + HBr
C2H6 + Br2 → C2H5Br + HBr
Did this page help you?
What is the correct IUPAC name and classification of the following molecule?
IUPAC name |
Classification |
|
A |
1,bromopentane |
Primary |
B |
2-bromopentane |
Secondary |
C |
2-bromopentane |
Primary |
D |
4-bromopentane |
Secondary |
Did this page help you?
Which of the following statements is not correct about the depletion of the ozone layer?
CFCs produce free radicals when they are exposed to UV light in the upper atmosphere
2 moles of ozone break down to form 3 moles of oxygen
Fluorine and chlorine free radicals can break down ozone molecules in the upper atmosphere
This is an example of a free radical substitution reaction
Did this page help you?
Three different halogenoalkanes are heated separately with aqueous silver nitrate, each reaction produced a precipitate.
Which halogenoalkane will produce a precipitate the fastest?
1-iodopropane
They precipitate at the same rate
1-chloropropane
1-bromopropane
Did this page help you?
What is meant by a nucleophile?
Electron pair donor
Electron pair acceptor
Proton donor
Proton acceptor
Did this page help you?
Which compound has the fastest rate of reaction with potassium hydroxide and ethanol to form an alcohol?
1- chlorobutane
1-bromobutane
1-fluorobutane
1-iodobutane
Did this page help you?
Which statement is not correct about ozone?
It decomposes to form oxygen
Ozone holes are regions of the upper atmosphere where there is a reduced concentration of ozone
Hydrofluorocarbons are more damaging to the ozone layer than chlorofluorocarbons
It absorbs ultraviolet radiation from the Sun
Did this page help you?
The equation for the hydrolysis of 1-iodopropane is shown below
CH3CH2CH2I + OH– →CH3CH2CH2OH + I –
What is the name of the mechanism used for this reaction?
Electrophilic Addition
Oxidation
Elimination
Nucleophilic substitution
Did this page help you?
CFCs contribute to ozone depletion in the upper atmosphere.
One CFC has the formula CF2Cl2
What is the shape of a CF2Cl2 molecule and the F-C-Cl bond angle?
Shape | F-C-Cl bond angle | |
A | pyramidal | 107° |
B | tetrahedral | 109.5° |
C | trigonal planar | 120° |
D | linear | 180° |
Did this page help you?
Why are haloalkanes more reactive than alkanes?
The carbon-halogen bond is non-polar
The carbon and halogen atoms have different electronegativities
Carbon–halogen bonds are stronger than carbon–hydrogen bonds
Carbon is more electronegative than the halogen
Did this page help you?
A chemist adds four drops of 1-chloropentane, 1-bromopentane and 1-iodopentane separately to three test-tubes containing 1.0 cm3 of aqueous silver nitrate at 60 °C. A hydrolysis reaction occurred.
Which statement best explains why 1-iodopentane precipitates first and 1-chloropentane precipitates last?
The bond polarity decreases from C-Cl to C-I
The electronegativity of the halogens decreases down the group
The bond enthalpy decreases from C-Cl to C-I
The ionisation energy of the halogens decreases from Cl to I
Did this page help you?
Which statement best describes the mechanism of the reaction between aqueous sodium hydroxide and 2-bromopropane?
Attack by a nucleophile on a carbocation
Attack by a nucleophile on a carbon atom with a partial positive charge
Homolytic bond fission and attack by a nucleophile on a carbocation
Homolytic bond fission and attack by an electrophile on a partial positive charge
Did this page help you?
In the hydrolysis of bromoethane by aqueous sodium hydroxide, what is the nature of the attacking species and of the leaving group?
Attacking group | Leaving group | |
A | nucleophile | nucleophile |
B | electrophile | nucleophile |
C | nucleophile | electrophile |
D | electrophile | electrophile |
Did this page help you?
Which reagents and conditions are required for the following reaction to take place?
CH3CH2CH2I → CH3CH2CH2OH
Heated under reflux, aqueous potassium cyanide
Heated under reflux, ethanol, potassium cyanide
Heated under reflux with aqueous sodium hydroxide
Warm with a solution of ethanol
Did this page help you?
Which pair of reactions shows the correct sequence of attack of CFC molecules with ozone?
Reaction 1 | Reaction 2 | |
A | F● + O3 → FO● + O2 | FO● + O3 → 2O2 + F● |
B | Cl + O3 → ClO● + O2 | ClO● + O3 → 2O2 + Cl |
C | Cl● + O3 → ClO● + O2 | ClO● + O3 → 2O2 + Cl● |
D | Cl● + O3 → ClO + O2 | ClO + O3 → 2O2 + Cl● |
Did this page help you?
What is the correct IUPAC name and classification of the following molecule?
IUPAC name | Classification | |
A | 2,methyl,2,bromobutane | Tertiary |
B | 3-methyl-3-bromobutane | Secondary |
C | 2-bromo-2-methylbutane | Secondary |
D | 2-bromo-2-methylbutane | Tertiary |
Did this page help you?
The presence of a halogen in an organic compound may be detected by warming the organic compound with aqueous sodium hydroxide and silver nitrate.
Which compound would be the quickest to produce a precipitate?
1,2,3-trichlorobutane
1,2-dichloro-3-fluorobutane
1,2-difluoro-3-iodobutane
1-bromo-2-chloro-3-fluorobutane
Did this page help you?
The breakdown of the ozone layer can be caused by NO• radicals.
Which equation is a propagation step in the mechanism for this process?
NO2• + O → NO• + O
NO• + O3 → NO2• + O2
O3 + O → 2O2
NO• + O2 → NO2• + O3
Did this page help you?
Dichlorodifluoromethane, CCl2F2, has been used in aerosol propellants and as a refrigerant.
Which statement helps to explain why dichlorodifluoromethane is chemically inert?
The carbon-fluorine bond energy is large
The carbon-fluorine bond has a low polarity
Fluorine is highly electronegative
Fluorine compounds are non-flammable
Did this page help you?
Which compound will not react with nucleophiles?
CH3CH2CH2OH
CH2CH2CHO
CH3CH2CH2Cl
CH3CH2CH2CH3
Did this page help you?
Which statements is/are correct about haloalkanes?
1, 2 and 3
Only 1 and 2
Only 2 and 3
Only 1
Did this page help you?
Which statements is/are correct?
1, 2 and 3
Only 1 and 2
Only 2 and 3
Only 1
Did this page help you?
Which statement is not correct about the reactions of haloalkanes?
Haloalkanes and alcohols both take part in dehydration reactions to produce alkenes
Haloalkanes are soluble in water due to the polar carbon-halogen bond.
The OH- nucleophile acts as a base in an elimination reaction.
Hot ethanolic NaOH is used to produce the nucleophile in a substitution reaction.
Did this page help you?
Which statements is/are not correct about the depletion of the ozone layer?
1, 2 and 3
Only 1 and 2
Only 2 and 3
Only 1
Did this page help you?
Which equation shows a propagation step in the depletion of the ozone layer by nitrogen oxide radicals?
NO• + •NO2 → N2O + O2
•NO2 + O3 → •NO + 2O2
N2 + O2 → •NO + •NO
•NO + O3 → NO2 + •O2
Did this page help you?