MCQ
A transition element $X$ has a configuration $\left[ {Ar} \right]3{d^4}$ in its $+ 3 $ oxidation state. Its atomic number is
- ✓$25$
- B$26$
- C$22$
- D$19$
✓
Answer
Correct option: A.
$25$
a
(a)Number of electrons in excited state
(a)Number of electrons in excited state
${X^{ + 3}} = 18 + 4 = 22$
Number of electrons in ground state
$X = 22 + 3 = 25$.
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