Some energy levels of a molecule are shown in the figure with their wavelengths of transitions. Then

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(d) : As, $\Delta E=E_i-E_f$ and $\lambda=\frac{h c}{\Delta E}$ $$ \begin{aligned} & \Delta E_1=\frac{-5 E}{2}-(-4 E)=\frac{3 E}{2} \ & \lambda_1=\frac{h c}{\Delta E_1}=\frac{2 h c}{3 E} \ & \Delta E_2=-2 E-(-3 E)=-2 E+3 E=E \ & \lambda_2=\frac{h c}{\Delta E_2}=\frac{h c}{E} \ & \Delta E_3=-2 E-(-4 E)=-2 E+4 E=2 E \ & \lambda_3=\frac{h c}{\Delta E_3}=\frac{h c}{2 E} \end{aligned} $$ From equation (i), (ii) and (iii) $\lambda_2>\lambda_1>\lambda_3 \quad$ and $\quad \lambda_2=2 \lambda_3$