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### Protons vs. Electrons

Posted: Tue May 08, 2018 3:49 pm
If a proton and an electron have the same wavelength, why does an electron travel faster?

### Re: Protons vs. Electrons

Posted: Tue May 08, 2018 3:54 pm
An electron travels faster than a proton because of its mass. If you rearrange the De Broglie equation, the total velocity is dependent on the mass of the particle, and electrons happens to be lighter than protons. I hope this helps!!

### Re: Protons vs. Electrons

Posted: Tue May 08, 2018 4:12 pm
Thank you so much, I really appreciate it! This is a different question but do you also know how to determine which atom will have a longer de Broglie wavelength? In question 3b of the Midterm Practice Exam it says that a Helium atom travels at the same speed as a Lyndonium atom, but a Lyndonium atom will have a longer wavelength.

### Re: Protons vs. Electrons

Posted: Tue May 08, 2018 7:51 pm
Lyndonium is said to have a De Broglie longer wavelength, because when you manipulate the De Broglie wavelength equation, you can conclude that the wavelength = h/mv. This equation tells you that the wavelength size is dependent on the mass of the element, because the problem is telling you that Helium is traveling at the same speed as Lyndonium (has the same velocity). The molar mass of Lyndonium is given in the problem, and it is larger than Helium so you can conclude that Lyndonium has a longer wavelength. I hope this helps!!

### Re: Protons vs. Electrons

Posted: Tue May 08, 2018 8:08 pm
Makes much more sense now, thanks again!