MCQ
Which of the following pairs involves isoelectronic ions
- A$M{n^{ + 3 }}$and $F{e^{+ 2}}$
- ✓$M{n^{ + 2}}$ and $F{e^{ + 3 }}$
- C$C{r^{+ 3 }}$ and $F{e^{ + 2}}$
- D$F{e^{+ 2}}$ and $C{o^{+ 2}}$
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| Energy level | $K$ | $L$ | $M$ | $N$ |
| $n=1$ | $n=2$ | $n=3$ | $n=4.....n=\infty$ | |
| Energy | $- 864 \,a.u.$ | Zero |
the excitation energy needed to raise the electron from $M$ level to $n = \infty$ would be :
