Question

Match the following
List-I (Elements)
A. Alkali metals
B. Alkaline earth metals
C. Halogens
D. Noble gases
List-II (Valence shell Configuration)
I. \( ns^2 np^6 \)
II. \( ns^2 np^5 \)
III. \( ns^2 \)
IV. \( ns^1 \)

• A. A - I, B - II, C - III, D - IV
• B. A - IV, B - III, C - II, D - I
• C. A - II, B - I, C - III, D - IV
• D. A - IV, B - I, C - III, D - II

Hint:

Recall the positions of the different groups of elements in the periodic table and their characteristic valence electron configurations. Alkali metals (Group 1) have one valence electron (\( ns^1 \)), alkaline earth metals (Group 2) have two valence electrons (\( ns^2 \)), halogens (Group 17) have seven valence electrons (\( ns^2 np^5 \)), and noble gases (Group 18) have a completely filled valence shell (\( ns^2 np^6 \)).

Answer 1

The Correct Option is B

We need to match the given elements with their respective valence shell electron configurations.
A.
**Alkali metals:** These are Group 1 elements in the periodic table.
Their valence shell configuration is \( ns^1 \), where \( n \) is the principal quantum number of the outermost shell.
Therefore, A matches with IV.
B.
**Alkaline earth metals:** These are Group 2 elements in the periodic table.
Their valence shell configuration is \( ns^2 \).
Therefore, B matches with III.
C.
**Halogens:** These are Group 17 elements in the periodic table.
Their valence shell configuration is \( ns^2 np^5 \).
They are one electron short of having a completely filled valence shell.
Therefore, C matches with II.
D.
**Noble gases:** These are Group 18 elements in the periodic table (except for Helium, which has \( 1s^2 \)).
They have a completely filled outermost shell, with a general valence shell configuration of \( ns^2 np^6 \).
This stable electron configuration makes them largely unreactive.
Therefore, D matches with I.
The correct matching is: A - IV B - III C - II D - I This corresponds to option (B).