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MHT CET 202625 AprilMorning Shift

Exam: MHT CET
Year: 2026
Date: 25 April
Shift: Morning Shift
Subject: Chemistry
Chapter: Structure of Atom

MHT CET 2026 · 25 April · Morning Shift · Chemistry · Structure of Atom

Which of the following elements has an electronic configuration,...

Which of the following elements has an electronic configuration,

[\text{Ar}]\ 4s^2

?

Options

A $\text{Na}$
B $\text{Mg}$
C $\text{K}$
D $\text{Ca}$

Correct answer

D. $\text{Ca}$

Step-by-step solution

The atomic number of Argon (

\text{Ar}

) is

18

.

The given electronic configuration is

[\text{Ar}]\ 4s^2

.

Total number of electrons

= 18 + 2 = 20

.

The element with atomic number

20

is Calcium (

\text{Ca}

).

Answer:

\text{Ca}

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