Final answer:
To find the energy of 1.20 mol of photons for visible light (515 nm), use the photon energy formula E = hc/λ and multiply the result by Avogadro's number and the number of moles.
Step-by-step explanation:
To determine the energy of photons for visible light with a wavelength of 515 nm, we can use the energy formula for photons, E = hc/λ, where h is Planck’s constant (6.626 x 10-34 J·s), c is the speed of light (3.00 x 108 m/s), and λ is the wavelength in meters. First, we need to convert the wavelength from nanometers to meters by multiplying by 10-9.
The energy for one photon is then calculated as follows:
E = (6.626 x 10-34 J·s)(3.00 x 108 m/s) / (515 x 10-9 m)
This computation yields a result with the energy of one photon. To obtain the energy of 1.20 mol of photons, we use Avogadro’s number (6.022 x 1023 photons/mol). The total energy is E_total = E x 1.20 mol x Avogadro’s number.