(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How many excess electrons are on a ball with a charge of -4.00*10^-17 C?

2. Relevant equations

I know that the charge per electron is 1.60 *10^-19C.

3. The attempt at a solution

My textbook does not explain how to do this, but I thought I would divide-->4.00*10^-17 C * 1 electron/-1.60*10^-19. I got -2.5*10^-36. The answer from the book is 2.5*10^2 electrons.

I did some messing around and did this-->4.00*10^-17C*1 e/1.60*10^19C=2.5*10^2 electrons.

What's the correct way to do this problem?

Thanks in advance.

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# Homework Help: How to find the number of excess electrons?

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