Question

The total energy of an electron in the ground state of hydrogen atom is $-13.6eV$. The potential energy of an electron in the ground state of $L{i}^{2+}$ ion will be

• A. $122.4eV$
• B. $-122.4eV$
• C. $244.8eV$
• D. $-244.8eV$

Answer 1

Answer: (D)

$-244.8eV$

Therefore, for ${Li}^{2+}$ ion, Total energy is $-13.6\times 9=122.4eV$
But, $-K.E=T.E=\frac{P.E}{2}$
Therefore, $P.E$ is $-244.8eV$