MCQ
General electronic configuration of outermost and penultimate shell is $(n -1)\, s^2 \,(n -1)p^6(n -1)\, d^x\, ns^2$. If $n = 4$ and $x = 5$, then number of protons in the nucleus will be :-
- A$> 25$
- B$< 24$
- ✓$25$
- D$30$
✓
Answer
Correct option: C.
$25$
c
$(n-1) s^{2}(n-1) p^{6}(n-1) d^{x} n s^{2}$
$(n-1) s^{2}(n-1) p^{6}(n-1) d^{x} n s^{2}$
If $\mathrm{n}=4 \quad \mathrm{x}=5$
$=3 s^{2} 3 p^{6} 3 d^{5} 4 s^{2}$
No. of protons $=25$
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