What is the energy in joules of a mole of photons associated with red light of wavelength 7.00 * 10² nm A) 4.72 * 10^-43 J B) 1.71 * 10⁵ J C) 12.4 kJ D) 256 kJ E) 2.12 * 10⁴² J

Question

Quizplus · Accepted Answer

The energy of a single photon can be calculated using the equation E = hc/λ, where h is Planck's constant, c is the speed of light, and λ is the wavelength of the light.

Plugging in the given values, we get:

E = (6.626 x 10^-34 J*s)(3.00 x 10^8 m/s)/(7.00 x 10^-7 m) 
E = 2.85 x 10^-19 J

This is the energy of one photon. To find the energy of a mole of photons (Avogadro's number, 6.022 x 10^23) we need to multiply by that number:

(2.85 x 10^-19 J/photon)(6.022 x 10^23 photons/mol) = 1.71 x 10^5 J/mol

Converting to scientific notation as shown in the answer choices, we get choice B as the correct answer.

What Is the Energy in Joules of a Mole of Photons