I have been trying to figure out these two problems and for some reason my logic or my math is wrong...please help.(adsbygoogle = window.adsbygoogle || []).push({});

1) What is the total charge (in C) on all the electrons in 7.0kg of water.

--what I did. 7000g/18g * 6.022E23 to give me the # of electrons (2.3419E26) then I plugged that into the N=q/e and got q= 37,470,222C. But according to our problem site it is wrong, so where did I go wrong?

2) A 2.0g Cu penny has a positive charge of 0.27millicoulombs. What decimal fraction of its electrons has it lost?

--what I did. 2g/63.546g 8 6.022E23 to get # of electrons it started with (1.895E22) then I plugged used the N=q/e (N= 0.27E-6C/1.6E-19 which came out to 1.6875E12) THen I divided 1.895E22/1.6875E12 to get 1.122E10, but the answer is incorrect.

I would truly apprecate ANY help.

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# Homework Help: Two charge problems

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