## CH.1 #33 pt B

mendozayael_2H
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### CH.1 #33 pt B

#1.33 says: "The velocity of an electron that is emitted from a metallic surface by a photon is 3.6 X 10^3 km/s. (a) What is the wavelength of the ejected electron? (b) No electrons are emitted from the surface of the metal until the frequency of the radiation reaches 2.50 X 10^16 Hz. How much energy is required to remove the electron from the metal surface?"

Chem_Mod
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### Re: CH.1 #33 pt B

Hello,

What part of the question do you not understand?

Elizabeth Bamishaye 2I
Posts: 54
Joined: Fri Sep 29, 2017 7:04 am

### Re: CH.1 #33 pt B

For part A, you determine the mass of electrons, which is $9.109\times 10^-31 kg$. Then you change the given velocity from kilometers to meters and after that use the equation $\lambda =h(m\nu )^{-1}$ or basically $\frac{h}{m\nu}$ to get the answer for part A.

For part b, you use $E= h\nu$ to get the answer for part B.

Clara Hu 1G
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### Re: CH.1 #33 pt B

For part b, use $E=\frac{1}{2}mv^{2}=h\nu -\phi$ . Because you know the velocity of the ejected electron and the frequency of the radiation, you can solve for the work function, which is the energy required to remove the electron, and get 1.66 x 10-17 J.