2025 Classification of Elements and Periodicity in PropertiesElectronic Configuration and Types of Elements Easy Question 6 of 41 in Classification of Elements and Periodicity in Properties

Which among the following electronic configurations belong to main group elements?
A. $[\text{Ne}]3s^1$
B. $[\text{Ar}]3d^3 4s^2$
C. $[\text{Kr}]4d^{10}5s^2 5p^5$
D. $[\text{Ar}]3d^{10}4s^1$
E. $[\text{Rn}]5f^0 6d^2 7s^2$
Choose the correct answer from the options given below:

A B and E only
B A and C only
C D and E only
D A, C and D only

The answer is B.

Solution

Main group elements belong to s- and p-blocks. A ($\text{Na}$, s-block) and C ($\text{I}$, p-block) are main group elements.

Main group (representative) elements are elements of the s-block and p-block (Groups 1, 2, and 13 to 18). Configuration A ($[\text{Ne}]3s^1$) is Sodium (Group 1, s-block). Configuration C ($[\text{Kr}]4d^{10}5s^2 5p^5$) is Iodine (Group 17, p-block). Configurations B (Vanadium) and D (Copper) are transition d-block elements, while E (Thorium) is an actinoid (f-block). Thus, only A and C belong to main group elements.

Concept Main Group Elements

Classification of Elements and Periodicity in Properties in past papers

41 questions from this chapter have appeared across 23 exam years.