Question

Is #5 right ?? I don’t understand net charge.

Answer 1

Net charge is the charge that the element has. Those are often used for forming ions mainly because all of them tend to be balanced.

Answer 2

Yes, since the number of protons is the same as the number of electrons. According to medical-dictionary.com, the net charge is, "the arithmetic sum of positive and negative charges," so I hope that definition makes it a little clearer for you. Hope I helped!