Your cart is empty.
Practice each question, then open the answer or worked solution.
Write IUPAC names of the following compounds:
(i) 2, 2, 4 -Trimethylpentan – 3 – ol
(ii) 5 – Ethylheptane – 2, 4 – diol
(iii) Butane – 2, 3 – diol
(iv) Propane – 1, 2, 3 – triol
(v) 2-Methylphenol
(vi) 4 – Methyl phenol
(vii) 2, 5 – Dimethylphenol
(viii) 2, 6 – Dimethylphenol
(ix) 1 – Methoxy – 2 – methyl propane
(x) Ethoxy benzene
(xi) 1 – Phenoxyheptane
(xii) 2 – Ethoxybutane
Write structures of the compounds whose IUPAC names are as follows:
(i) 2 – Methylbutan – 2 – ol
(ii) 1 – Phenylpropan – 2 – ol
(iii) 3 , 5 – Dimethylhexane – 1 , 3 , 5 – triol
(iv) 2, 3 – Diethylphenol
(v) 1 – Ethoxypropane
(vi) 2 – Ethoxy – 3 – methylpentane
(vii) Cyclohexylmethanol
(viii) 3 – Cyclohexylpentan – 3 – ol
(ix) Cyclopent – 3 – en – 1 – ol
(x) 4-Chloro-3-ethylbutan-1-ol.
(i) Draw the structures of all isomeric alcohols of molecular formula C5H12O and give their IUPAC names.
(ii) Classify the isomers of alcohols in question.
(i) The structures & IUPAC names of all isomeric alcohols with a molecular formula of C5H12O are shown below:
(a) CH3-CH2-CH2-CH2-CH2-OH
Pentan – 1 – ol (1 °)
2 – Methylbutan – 2 – ol ( 3 ° )
(ii) Primary alcohol: Pentan – 1 – ol ; 2 – Methylbutan – 1 – ol ;
3 – Methylbutan – 1 – ol ; 2, 2 – Dimethylpropan – 1 – ol
Secondary alcohol: Pentan – 2 – ol ; 3 – Methylbutan – 2 – ol ;
Pentan – 3 – ol
Tertiary alcohol: 2 – methylbutan – 2 – ol
Explain why propanol has higher boiling point than that of the hydrocarbon, butane.
The presence of – OH group makes Propanol undergo intermolecular H-bonding. Butane, while on the other side does not have the same privilege
Hence, additional energy would be required to break the intermolecular hydrogen bonds.
This is the reason why hydrocarbon butane has a lower boiling point than propanol.
Alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses. Explain this fact.
Due to the presence of – OH group, alcohols form H – bonds with water.
As a result, alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses.
What is meant by the hydroboration-oxidation reaction? Illustrate it with an example.
The hydroboration – oxidation reaction is the reaction where borane is added in order for the oxidation to take place. For example, propan – 1 – ol is formed by making propene undergo the hydroboration – oxidation reaction. In the above reaction, the reaction between propene and diborane ( BH 3 )2 takes place in order to form trialkyl borane which acts an additional product. This additional product is oxidized to alcohol by hydrogen peroxide in the presence of aqueous sodium hydroxide.
Give the structures and IUPAC names of monohydric phenols of molecular formula, C7H8O.
Solution coming soon.
While separating a mixture of ortho and para nitrophenols by steam distillation, name the isomer which will be steam volatile. Give reason.
Intramolecular H – bonding is present in o – nitrophenol & p – nitrophenol. In p – nitrophenol, the molecules are strongly associated due to the existence of intermolecular bonding.
Therefore, o – nitrophenol is steam volatile.
Give the equations of reactions for the preparation of phenol from cumene.
To synthesize phenol, cumene is initially oxidized in the presence of air of cumene hydroperoxide.
Followed by, treating cumene hydroxide with dilute acid to prepare phenol & acetone as byproducts.
Write the mechanism of hydration of ethene to yield ethanol.
There are three steps that are involved in the mechanism of hydration of ethene to form ethanol. these steps are as follows:
Step 1 :
Protonation of ethene to form carbocation by an electrophilic attack of H3 O + :
Step 2:
Nucleophilic attack of water on carbocation :
Step 3:
Deprotonation to form ethanol :
