The energies E₁ and E₂ of two radiations are 25 eV and 50 eV respectively. The relation between their wavelengths i.e., ${\mathrm{\lambda }}_1$ and ${\mathrm{\lambda }}_2$ will be:

1.  ${\mathrm{\lambda }}_1=2{\mathrm{\lambda }}_2$

2.  ${\mathrm{\lambda }}_1=4{\mathrm{\lambda }}_2$

3.  ${\mathrm{\lambda }}_1=\frac{1}{2}{\mathrm{\lambda }}_2$

4.  ${\mathrm{\lambda }}_1={\mathrm{\lambda }}_2$

If the energy of the second Bohr orbit of the hydrogen atom is –328 kJ mol^–1, the energy of the fourth Bohr orbit would be:

The radius of a hydrogen shell is 0.53Å. In its first excited state, radius of the shell will be:
1. 2.12 Å
2. 1.06 Å
3. 8.5 Å
4. 4.24 Å