(b) $\mathrm{\Delta}E = 13.6Z^{2\ }\left( \frac{1}{n_{1}^{2}} - \frac{1}{n_{2}^{2}} \right)$ = 13.6 (3)$^{2}$$\left\lbrack \frac{1}{1^{2}} - \frac{1}{3^{2}} \right\rbrack$ =108.8 $e$V
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.