Question 436: Atoms & Nuclei

Question

In the second orbit of hydrogen atom, the energy of an electron is ' $E$ '. In the third orbit of helium atom, the energy of the electron will be (atomic number of helium $=2$)

Accepted Answer

$$\begin{aligned}
\quad \mathrm{E} & \propto \frac{\mathrm{Z}^2}{\mathrm{n}^2} \
	herefore \quad \frac{\mathrm{E}_{\mathrm{H}}}{\mathrm{E}_{\mathrm{He}}} & =\frac{\left(\mathrm{Z}^2ight)_{\mathrm{H}}}{(\mathrm{n})_{\mathrm{H}}^2} 	imes \frac{\left(\mathrm{n}_{\mathrm{He}}ight)^2}{\left(\mathrm{Z}^2ight)_{\mathrm{He}}} \
& =\frac{1}{2^2} 	imes \frac{3^2}{2^2}=\frac{9}{16} \
	herefore \quad E_{\mathrm{He}} & =\frac{16}{9} E_{\mathrm{H}}=\frac{16}{9} \mathrm{E}
\end{aligned}$$

Answer

$\frac{4 \mathrm{E}}{9}$

Answer

$\frac{4 \mathrm{E}}{3}$

Answer

$\frac{16 \mathrm{E}}{9}$

Answer

$\frac{16 \mathrm{E}}{3}$

Atoms & Nuclei

In the second orbit of hydrogen atom, the energy of an electron is ' E '. In the third orbit of helium atom, the energy of the electron will be (atomic number of helium =2)

Choose the correct answer: