Answer
Verified
380.1k+ views
Hint: The less electronegative the element, the less stable the lone pair will be and therefore the higher will be its basicity. Another useful trend is that basicity decreases as you go down a column of the periodic table. This is because the valence orbitals increase in size as one descends a column of the periodic table.
Complete answer:
Comparing the other two to ammonia, you will see that methylamine is a stronger base, whereas phenyl amine is very much weaker. All aliphatic primary amines are stronger bases than ammonia. Phenyl amine is typical of aromatic primary amines where the $ - N{H_2}$ group is attached directly to a benzene ring.
Amines are basic because they possess a pair of unshared electrons, which they can share with other atoms. These unshared electrons create an electron density around the nitrogen atom. The more basic the molecule the greater is the electron density.
The basicity of $N$ in ammonia, anilines attached to $N$ depends on the availability of the lone-pair of electrons on $N$. An aromatic ring is electron withdrawing and reduces the availability of the lone-pair of electrons on $N$, thereby reducing the basicity. In contrast, aliphatic carbons are electron donating, increasing the availability of the lone-pair on $N$ and thereby increasing the basicity.
Note:
Remember if there is an aromatic group in the molecule but not directly attached to the nitrogen of the amine. In this case, the amine will be more basic but not by much. For example, the\[p{K_a}\]of benzyl amine is $4.66$, slightly more basic than ammonia.
Complete answer:
Comparing the other two to ammonia, you will see that methylamine is a stronger base, whereas phenyl amine is very much weaker. All aliphatic primary amines are stronger bases than ammonia. Phenyl amine is typical of aromatic primary amines where the $ - N{H_2}$ group is attached directly to a benzene ring.
Amines are basic because they possess a pair of unshared electrons, which they can share with other atoms. These unshared electrons create an electron density around the nitrogen atom. The more basic the molecule the greater is the electron density.
The basicity of $N$ in ammonia, anilines attached to $N$ depends on the availability of the lone-pair of electrons on $N$. An aromatic ring is electron withdrawing and reduces the availability of the lone-pair of electrons on $N$, thereby reducing the basicity. In contrast, aliphatic carbons are electron donating, increasing the availability of the lone-pair on $N$ and thereby increasing the basicity.
Note:
Remember if there is an aromatic group in the molecule but not directly attached to the nitrogen of the amine. In this case, the amine will be more basic but not by much. For example, the\[p{K_a}\]of benzyl amine is $4.66$, slightly more basic than ammonia.
Recently Updated Pages
what is the correct chronological order of the following class 10 social science CBSE
Which of the following was not the actual cause for class 10 social science CBSE
Which of the following statements is not correct A class 10 social science CBSE
Which of the following leaders was not present in the class 10 social science CBSE
Garampani Sanctuary is located at A Diphu Assam B Gangtok class 10 social science CBSE
Which one of the following places is not covered by class 10 social science CBSE
Trending doubts
Harsha Charita was written by A Kalidasa B Vishakhadatta class 7 social science CBSE
Which are the Top 10 Largest Countries of the World?
Banabhatta wrote Harshavardhanas biography What is class 6 social science CBSE
Difference Between Plant Cell and Animal Cell
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE
How do you graph the function fx 4x class 9 maths CBSE
The Equation xxx + 2 is Satisfied when x is Equal to Class 10 Maths
One Metric ton is equal to kg A 10000 B 1000 C 100 class 11 physics CBSE
Why is there a time difference of about 5 hours between class 10 social science CBSE