MCQ
What may be the first ionisation energy of $Na$ if it has effective nuclear charge of $1.84$ assuming Bohr model of $H$-atom to be effective on it ............. $\mathrm{eV}$
- A$13.6$
- B$46$
- C$1.51$
- ✓$5.1$
✓
Answer
Correct option: D.
$5.1$
d
$I.E.$ $=\frac{13.6(1.84)^{2}}{3^{2}}=5.11 \,\mathrm{eV}$
$I.E.$ $=\frac{13.6(1.84)^{2}}{3^{2}}=5.11 \,\mathrm{eV}$
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