Q51 / 180 · NEET 2013 (Karnataka) · Chemistry
According to law of photochemical equivalence the energy absorbed (in erg/ mole $)$ is given as $\left(h=6.62 \times 10^{-27}\right.$ ergs, $\mathrm{c}=3 \times 10^{10} \mathrm{~cm} \mathrm{~s}^{-1}, \mathrm{~N}_{\mathrm{A}}=6.02 \times 10^{-23}$ $\left.\mathrm{mol}^{-1}\right)$ :
- Correct answerA$\frac{1.196 \times 10^8}{\lambda}$
- B$\frac{2.859 \times 10^5}{\lambda}$
- C$\frac{2.859 \times 10^{16}}{\lambda}$
- D$\frac{1.196 \times 10^{16}}{\lambda}$
Solution
$$
\begin{aligned}
& \mathrm{E}=\frac{h c \mathrm{~N}_{\Lambda}}{\lambda} \\
& =\frac{6.62 \times 10^{-27} \times 3 \times 10^{10} \times 6.02 \times 10^{23}}{\lambda} \\
& =\frac{1.196 \times 10^8}{\lambda} \mathrm{ergs} / \mathrm{mol}
\end{aligned}
$$
Hence, the correct answer is option: 'A'.