Final answer:
The energy of the hydrogen emission spectrum line at a wavelength of 625 nm is 3.187 x 10^-19 joules.
Step-by-step explanation:
The energy of a photon can be calculated using the equation E = hc/λ, where E represents energy, h is Planck’s constant (6.626 x 10^-34 J·s), c is the speed of light (3.00 x 10^8 m/s), and λ is the wavelength of the radiation in meters.
In this case, we need to convert the wavelength from nanometers to meters. The wavelength of 625 nm is equivalent to 625 x 10^-9 meters. Plugging this value into the equation, we get:
E = (6.626 x 10^-34 J·s)(3.00 x 10^8 m/s)/(625 x 10^-9 m) = 3.187 x 10^-19 J
Therefore, the energy of the radiation is 3.187 x 10^-19 joules.