3. An unknown element produces a spectral line of 425nm.
A. Calculate the energy of the emitted photon in joules.
B. What is the energy of the emitted photon in electron-volts?
To calculate the energy of the emitted photon in joules, you can make use of the equation:
E = hc/λ,
where E is the energy of the photon, h is Planck's constant (which is approximately 6.626 x 10^-34 joule-seconds), c is the speed of light (approximately 3 x 10^8 meters per second), and λ is the wavelength of the spectral line.
A. Calculate the energy of the emitted photon in joules:
Plugging in the values, we have:
E = (6.626 x 10^-34 J·s)(3 x 10^8 m/s) / 425 x 10^-9 m
E ≈ 4.93 x 10^-19 joules
So, the energy of the emitted photon in joules is approximately 4.93 x 10^-19 J.
To calculate the energy of the emitted photon in electron-volts (eV), you can use the conversion factor:
1 eV = 1.602 x 10^-19 J.
B. Calculate the energy of the emitted photon in electron-volts:
Divide the energy in joules by the conversion factor:
(4.93 x 10^-19 J) / (1.602 x 10^-19 J/eV) ≈ 3.08 eV
So, the energy of the emitted photon in electron-volts is approximately 3.08 eV.