## Defining eV

Isaac Wen
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### Defining eV

Hi!

I was just wondering what exactly is the unit eV and why it's being used in many of the problems we see (instead of the SI unit J). How is it related to J and do we have to convert it to J every time we have to calculate something energy-related?

Bella Bursulaya 3G
Posts: 149
Joined: Wed Sep 30, 2020 9:54 pm

### Re: Defining eV

Hi! So Professor Lavelle mentioned that the eV is the amount of kinetic energy that an electron gains from moving across an electric potential difference of 1 volt.

The conversion is 1.602 x 10^-19 J. I am unsure if we need to memorize this, however, if you work with it enough, you'll end up memorizing it haha!

Bella Bursulaya 3G
Posts: 149
Joined: Wed Sep 30, 2020 9:54 pm

### Re: Defining eV

Sorry I forgot to answer the second part of your question. We do need to convert from eV to J I am pretty sure, to make sure all of our units cancel out!

Chem_Mod
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### Re: Defining eV

The conversion between eV and Joules will be given on the formula sheet.

Kelly Yun 2I
Posts: 117
Joined: Wed Sep 30, 2020 10:03 pm

### Re: Defining eV

Would there be an equation for this topic that would not be on the formula sheet but one that we would have to know?

805377003
Posts: 113
Joined: Wed Sep 30, 2020 10:10 pm

### Re: Defining eV

The conversion is 1.602 x 10^-19 J.