Question

Which of the following illustrate the anomalous properties of lithium?
A.Lithium is softer than other group metals
B.Lithium forms nitride, $L{i_3}N$unlike other group I metals
C.The melting and boiling point are comparatively high
D.None of these

Answer 1

We must know that lithium is a chemical element having the symbol Li and its atomic number is three. And it is readily reacted with water and there is a formation of corrosive bases. The lithium is used in mobile phones, electric vehicles, cameras and laptops as rechargeable batteries. And it also has several industrial applications. It has the lowest density among all the metals.

Complete answer:
Lithium is not a soft metal, and it is harder than other group metals. Hence, option (A) is incorrect.
Lithium forms nitride, $L{i_3}N$ unlike other group I metals. Because, the lithium is directly reacted with the nitrogen and there is a formation of lithium nitride due to the small size of lithium ion. And is easily reacted with ${N^{3 - }}$ ion. A high amount of lattice energy is released during the reaction and it is an exothermic reaction. And the nitride is highly stable. The reaction can be written as,
$6Li + {N_2} \to 2L{i_3}N$
Hence, option (B) is correct.
The melting and boiling point are comparatively high. Because, the relative ionization enthalpy of lithium is very high because of its small size. Moreover, in crystal lattice, the binding energy of lithium is very high. Therefore, the boiling point and melting point of lithium are comparatively higher than other group metals.
Hence, option (C) is correct.
The lithium forms nitride and its melting and boiling point is higher than other group metals. Thus, option B and C are true. Hence, the option (D) is incorrect.

Note:
We must have to know that lithium is a chemical element and it has a very small size. Due to its smaller size, the ionization energy is very high. Therefore, it is easily reacted with nitrogen and there is a formation of lithium nitride. And the melting point and boiling point of lithium is very high. And lithium is not a soft metal, it is harder than other metals which are found in the same group, (alkali metals).