Question

If light has a wavelength of 525 nm, what is the energy of this light expressed with units of kJ/mol?
     kJ/mol

Part 2   (0.5 point)

See Hint

A beam of radiation has an energy of 2.47×10² kJ/mol. What is the wavelength of this light?
     nm

Answer 1

The relation between the energy of light and its wavelength is as follows: E = ... (1) (1) Energy emitted, E = ? Plank's cosntant, h = 6.626x 10-34 Js velocity of light, c = 3.00x10 m/s 10* m wavelength, 1 = 525 nm = 525 nm x 525x109 m 1 nm Substitute the corresponsing valuesin equation (1) and calculate the energy E-6.626x10-* Jsx3.00×108 m/s 525x10 m 1kJ E = 0.0378x10-1? Jx "1000J E = 0.0378x10-20 11 E = 3.78x10-22 kJ The above energy calculated is for 1 photon. According to avadagros number, in one mole there are 6.022x10 photons Energy, E = 3.78x10-2_IJ 6.022x102 photons photon 1 mol = 22.8x10 kJ/mol = 228 kJ/mol Therefore, the required solution is 228kJ/mol - - - - (2) Given, energy, E = 2.47x109 kJ/mol Plank's cosntant, h = 6.626x10-34 Js velocity of light, c = 3.00x10 m/s wavelength, 1 = ? Substitute the corresponsing valuesin equation (1) and calculate 2. a= ho 6.626x10-* Js x 3.00x109 m/s 2.47x109 kJ/mol 1kJ 6.022x1022 photons 10T1 mol 1 mol 1 = 48.5x10my Inm 1 = 485 nm Therefore, the required solution is 485 nm)