Question

Time taken to produce 1 mol of photon by a 100 W $\left(J{s}^{-1}\right)$ yellow lamp is:

(given $\lambda$ of yellow light is 560 nm)

• A. $340min$
• B. $12min$
• C. $36min$
• D. $40min$

Answer 1

The correct option is C $36min$

Energy of 1 mole of photon $=\frac{N_{A}hc}{\lambda }$$=\frac{6.023\times {10}^{23}\times 6.62\times {10}^{-34}\times 3\times {10}^8}{560\times {10}^{-9}}=213.69\times {10}^{3}J$
Time taken for this energy $=\frac{213.6\times {10}^{3}J}{100J{s}^{-1}}=2136s=36min.$