Advertisements
Advertisements
प्रश्न
Give a plausible explanation for the following:
Why do primary amines have higher boiling points than tertiary amines?
उत्तर
In a molecule of tertiary amine, there are no H-atoms whereas in primary amines, two hydrogen atoms are present. Due to the presence of H-atoms, primary amines undergo extensive intermolecular H-bonding. As a result, extra energy is required to separate the molecules of primary amines. Hence, primary amines have higher boiling points than tertiary amines.
\[\begin{array}{cc}
\ce{H}\phantom{.............}\ce{H}\phantom{............}\ce{H}\phantom{....}\\
\phantom{...}|\phantom{..............}|\phantom{.............}|\phantom{.......}\\
\ce{\text{- - - - - -} N-H \text{- - - - - -} N-H \text{- - - - - -} N-H \text{- - - - - -}}\\
\phantom{...}|\phantom{..............}|\phantom{.............}|\phantom{.......}\\
\ce{\underset{Primary Amine}{R\phantom{.............}R\phantom{............}R\phantom{....}}}
\end{array}\]
\[\begin{array}{cc}
\ce{R}\phantom{....}\\
|\phantom{....}\\
\ce{N-R}\\
|\phantom{....}\\
\ce{\underset{Tertiary amine}{R}}\phantom{....}
\end{array}\]
APPEARS IN
संबंधित प्रश्न
Primary and secondary nitroalcanes containing α - H atom show property of -
- chain isomerism
- tautomerism
- optical isomerism
- geometrical isomerism
What is the action of nitrous acid on primary nitroalkane?
Describe a method for the identification of primary, secondary and tertiary amines. Also write chemical equations of the reactions involved.
When primary amine reacts with CHCl3 in alcoholic KOH, the product is _______.
(A) aldehyde
(B) alcohol
(C) cyanide
(D) an isocyanide
What is the action of nitrous acid on secondary nitroalkane?
What is the action of nitrous acid on tertiary nitroalkane
Describe Hinsberg method for the identification of primary, secondary and tertiary amines. Also write the chemical equations of the reactions involved.
Which of the following reactions will not give a primary amine?
Identify the compound that will react with Hinsberg’s reagent to give a solid which dissolves in alkali.
Identify the compound that will react with Hinsberg’s reagent to give a solid which dissolves in alkali.
Given below are two statements labelled as Assertion (A) and Reason (R).
Assertion (A): Tertiary amines are more basic than corresponding secondary and primary amines in gaseous state.
Reason (R): Tertiary amines have three alkyl groups which cause +I effect.
Select the most appropriate answer from the options given below:
Compound A is converted to B on reaction with CHCl3 and KOH. The compound B is toxic and can be decomposed by C. A, B and C respectively are ______.
The presence of primary amines can be confirmed by ______.
Which of the following is not a correct statement for primary aliphatic amines?
Match List I with List II.
| List I | List II | ||
| (A) | Benzenesulphonyl chloride | (I) | Test for primary amines |
| (B) | Hoffmann bromamide reaction | (II) | Anti Saytzeff |
| (C) | Carbylamine reaction | (III) | Hinsberg reagent |
| (D) | Hoffmann orientation | (IV) | Known reaction of Isocyanates |
Choose the correct answer from the options given below:
Give reasons:
(CH3)2NH is more basic than (CH3)3N in an aqueous solution.
Carbylamine test is the distinguishing test for ______.
