Originally Posted by **Ace** Calculate the net charge on a substance consisting of a combination of 7.8 1013 protons and 3.0 1013 electrons. |

I think you could have gotten this one on your own. There are 6.2415X10^18 charged particles per Coloumb. There are (7.8 - 3)X10^13 net charged particles, therefore the net charge on the substance is (4.8X10^13/6.2415X10^18) Coloumbs.

That is about 7.69 microColoumbs.

I hope that's what you were looking for.

Many Smiles

Craig