## Post-Module Question #20 [ENDORSED]

$\Delta p \Delta x\geq \frac{h}{4\pi }$

Jasmine Wu 1L
Posts: 55
Joined: Thu Jul 27, 2017 3:00 am
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### Post-Module Question #20

Hello! I'm having some trouble doing #20 from the Heisenberg Indeterminacy Equation post-module.

Use the above uncertainty in velocity (which I calculated to be delta v = 3.4*10^10 m/s) to calculate the electron's uncertainty in kinetic energy. Then calculate the uncertainty in kinetic energy per mole of electrons (that is, per mole of hydrogen atoms).

How would I calculate the kinetic energy and then its uncertainty per mole of electrons?

Thanks!

James Nguyen 3G
Posts: 19
Joined: Sat Jul 22, 2017 3:00 am

### Re: Post-Module Question #20  [ENDORSED]

I believe that you would use the equation K = 1/2mv^2 to find kinetic energy, using delta v and the mass of an electron then multiply this by avogadro's constant.

Tylor McGrew 1J
Posts: 20
Joined: Fri Sep 29, 2017 7:03 am

### Re: Post-Module Question #20

Kinetic Energy = (1/2)(9.109x10^-31 kg)(3.4x10^10)^2
= 5.3 x 10^-10 J/e
(5.3x10^-10) x (6.022 x 10^23) = 3.2 x 10^14 J/mol