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nelleL0ela3Marrello
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16) How many photons are contained in a burst of yellow light (589 nm) from a sodium lamp that contains 609 kJ of energy?

A3.37 × 1019 photons
B3.06 × 1030 photons
C1.81 × 1024 photons
D4.03 × 1028 photons
E2.48 × 1025 photons

Verified Answer :

The correct answer to this question is this one:

find the energy of one photon:

E=hc/λ

divide the energy given by the energy of one photon of that wavelength

What I've done so far is convert wave length to m and energy to j. 

E photon = h x / wave length
E = (6.626 x 10^-43)(3.00 x 10^8) / 587 ^ -9  = 3.38 x 10 ^18 J
3.38 x 10 ^18 J x 1000 kj / 1 j = 3.37 x 10 ^ 16 Kj
609 kJ/  3.37 x 10 ^ 16 Kj =  1.81 x 10 ^ 16

E = (6.626 x 10^-34)(3.00 x 10^8) / 587 ^ -9 = 3.38 x 10 ^19 J
3.38 x 10 ^19 J x 1000 kj / 1 j = 3.37 x 10 ^ -16 Kj
609 kJ/ 3.37 x 10 ^ 16 Kj = 1.81 x 10 ^ 18 but the answer is  1.81 × 10^24 photons

3.38 x 10 ^-19 J
should be negative

then 3.38 x 10 ^18 J x 1kJ/1000 J

you're converting from J to kJ.. just like meters to kilometres, you wouldn't multiply you would divide

Answer:  C) \(1.81\times 10^{24}\) photons

Explanation:

\(E=\frac{nhc}{\lambda}\)

E= energy = 609 kJ = 609000 J    (1kJ=1000J)

\(n\) = number of photons = ?

h = Planck's constant  = \(6.626\times 10^{-34}Js\)

c = speed of light = \(3\times 10^8m/s\)

\(\lambda\) = wavelength of photon = 589 nm =\(589\times 10^{-9}m\)

Putting values in above equation, we get:

\(609000J=\frac{n\times (6.626\times 10^{-34}Js)\times (3\times 10^8m/s)}{589\times 10^{-9}m}\)

\(n=1.81\times 10^{24}\)

Thus there are \(1.81\times 10^{24}\) photons in a burst of yellow light (589 nm) from a sodium lamp that contains 609 kJ of energy.

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