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3 years ago

How many photons are contained in a flash of green light (525 nm) that contains 189 kJ of energy?

Chemistry

1 answer:

adelina 88 [10]3 years ago

4 0

Answer: 4.99×10²³ photons

Explanation: The energy of a photon is given as

E= hf

h= Planck constant = 6.626×10^-34Js

f= frequency = c/x

C= speed of light = 3×10^8 m/s

x= wavelength= 525nm= 525×10^-9

E= hc/x

E= 6.626×10^-34 × 3×10^8 m/s /( 525×10^-9)

E= 3.79×10^−19 J/ Photon

E= 3.79×10^−22KJ/Photon

189KJ/3.79×10^−22KJ/photon=

4.99×10²³photons.

Therefore the number of photons is

4.99×10²³photons.

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3 years ago

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3 years ago

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dybincka [34]

Answer C
I could be wrong
Explanation

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4 years ago

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Basile [38]

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I was actually learned about this in school just found an source.

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