### 1.34

Posted:

**Sat May 05, 2018 11:59 pm**1.34 The work function for chromium metal is 4.37 eV. What wavelength of radiation must be used to eject electrons with a velocity of 1.5 103 kms1?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=16&t=31388

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Posted: **Sat May 05, 2018 11:59 pm**

1.34 The work function for chromium metal is 4.37 eV. What wavelength of radiation must be used to eject electrons with a velocity of 1.5 103 kms1?

Posted: **Sun May 06, 2018 3:33 am**

Energy of the photon of radiation=work function+kinetic energy of the electron

1) Convert 4.37 eV to J using 1 eV=1.602x10-19 J. This is the work function.

2) Find the kinetic energy of the electron by using Ek=1/2*m*v^2.

3) Add the work function and the Ek(kinetic energy) together to get the energy of the photon.

4) Use E=hc/lambda to find lambda (the wavelength of the light).

1) Convert 4.37 eV to J using 1 eV=1.602x10-19 J. This is the work function.

2) Find the kinetic energy of the electron by using Ek=1/2*m*v^2.

3) Add the work function and the Ek(kinetic energy) together to get the energy of the photon.

4) Use E=hc/lambda to find lambda (the wavelength of the light).

Posted: **Thu Jun 14, 2018 1:01 pm**

I did the steps but I still got something different...