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Grade 12Physical Chemistry

When electromagnetic radiation of wavelength 300 nm falls on the surface of sodium, electrons are emitted with a kinetic energy of 1.68 ×105 J mol–1. What is the minimum energy needed to remove an electron from sodium? What is the maximum wavelength that will cause a photoelectron to be emitted

Profile image of sudhanshu
12 Years agoGrade 12
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1 Answer

Profile image of Gaurav
11 Years ago
Hello Student
E = hv = hc/v
Putting the values we get,
E = 6.62 X 10-19 J
So, the enery for one mole of photons = 6,62 x 10-19 x6.62 X 10-19J = 3,99 x 105J
So, minimum amount of energy required = 2.31 x 105 j