A particular x-ray has a wavelength of 1.5 Å. Calculate the energy (in J) of one photon of this radiation.?

Answer 1

It seems to me that you have trouble in electro-photon reaction. Please memorize the formula between the energy and frequency or wavelength.
To convert energy to frequency or wavelength, we have to use the following formula:
E = h•ν = h•c/λ
where E the energy in Joule, h the Plank constant 6.626x10^-34 J•s, ν the frequency in 1/s, c the speed of light 2.998x10^8m/s, and λ the wavelength in m (1nm = 10^-9m). Now please do the math.