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1. An excited lithium atom emits a red light with wavelength a = 671nm. What is the corresponding photon energy? hc (6.63 x 10-34).S)(3.0 x 108m/s)​

User PankajSanwal
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1 Answer

14 votes
14 votes

Answer:

E = 2,964 10⁻¹⁹ J

Step-by-step explanation:

The energy of the photons is given by the Planck relation

E = h f

the speed of light is related to wavelength and frequency

c = λ f

we substitute

E = h c /λ

let's reduce the magnitude to the SI system

λ = 671 nm = 671 10⁻⁹ m

let's calculate

E = 6.63 10⁻³⁴ 3 10⁸ /671 10⁻⁹

E = 2,964 10⁻¹⁹ J

User Dudi
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