# Homework Help: How many electrons does the atom have?

Tags:
1. Sep 9, 2015

### pandamonium786

1. The problem statement, all variables and given/known data
A neutral atom is known to have a nucleus with a positive charge of 2.4 x10-12 C. How many electrons does the atom have?
2. Relevant equations
q=Ne

3. The attempt at a solution
None

2. Sep 9, 2015

### Greg Bernhardt

What have you tried? Where are you stuck?

3. Sep 9, 2015

### pandamonium786

I tried finding out the amount of protons by multiplying 2.4 x 10^ -12 C by the amount of electrons in a coulomb 6.25 x 10^18. But then I got confused. So I would like to know how to get the answer and why that is the answer. Also I know the solution but not how to get there, the solution is 1.5 x107 electrons

4. Sep 9, 2015

### LittleMrsMonkey

What does it mean that the atom is neutral?Let's start there.
Also,in case you aren't aware,the charge of the electron(e) is a given.

5. Sep 9, 2015

### pandamonium786

That means the electrons and protons balance each other out. Or in other words the whole atom has a neutral charge.

6. Sep 9, 2015

### LittleMrsMonkey

What information about the electrons can you gain from what you just said?

7. Sep 9, 2015

### pandamonium786

That the electrons and protons will be equal in amount or charge?

8. Sep 9, 2015

### LittleMrsMonkey

Great!Can you calculate the number of electrons now?

9. Sep 9, 2015

### SteamKing

Staff Emeritus
Are you sure the positive charge is 2.4×10-12 Coulombs? That's a lotta protons for one atom!

https://en.wikipedia.org/wiki/Proton

10. Sep 9, 2015

### pandamonium786

1.5 x 10^7 electrons. Thank you so much I get it now. :D

11. Sep 9, 2015

### SteamKing

Staff Emeritus
You've just calculated a meaningless number. Which atom has 15 million electrons orbiting the nucleus???

Hint: the natural elements have from 1 to 92 electrons per atom.

12. Sep 9, 2015

### LittleMrsMonkey

Well that's true,but I guess what matters is he understood how to get there.

13. Sep 9, 2015

### Bystander

Does the original problem statement maybe have a "μ" preceding the "C"? As in "micro-coulomb?"

14. Sep 9, 2015

### SteamKing

Staff Emeritus
Yeah, but the physics student should be aware of when he is calculating a reasonable result and when he is calculating nonsense.