Question

X-ray photons with a wavelength of 0.135 nm . express the energy numerically in kilojoules per mole.

Answer 1

Answer:

884.9×10^3 KJ mol-1

Explanation:

From E= hf

E= Energy of the photon

h= Plank's constant

f= frequency of the radiation

But f= c/λ

c= speed of light

λ= wavelength

Hence

E= hc/λ

E= 6.63×10^-34 × 3×10^8/135×10^-12

E= 147×10^-17 × 6.02×10^23

E= 884.9×10^3 KJ mol-1

Answer 2

Using E=hν where h is Planck's constant and v is the frequency of the photon. In the question above,the wavelenght is given so we can find the frequency of the photon using c=λν. c is a constant =3*10^8 so frequency is equal to
(3*10^8)/0.135*10^-9. Then use ur frequency in the eqn above using h 6.626*10^-34