How many protons are in an ion with 86 electrons and a −1 charge? & How many total electrons are in a Ni2+ ion?

Question

How many protons are in an ion with 86 electrons and a −1 charge?

1. number of protons:?

How many total electrons are in a Ni2+ ion?

1. number of electrons:?

Answer 1

Ionic charges for ions and ionic molecules are based on the net charge of the combined protons (+) and electrons (-). The neutrons do not affect the net charge because they have a neutral charge (0). So with this in mind we can create a formula based on the number of protons and electrons: p - e = charge. Where p is the number of protons and e is the number of electrons.

So if an ion had 86 electrons and a -1 charge we could rearrange the equation to find out how many protons are in the ion: p = e + charge. So substituting with our values we get p = 86 - 1 = 85. On the periodic table the atom with 85 protons is Astatine (At).

Now in order to find the number of electrons in a Ni²⁺ ion we need to know how many protons are in Ni. According to the periodic table Ni has 28 protons in its neutral state (Ni⁰). So to rearrange the equation we get: e = p - charge. Substituting our values into the equation will give us: e = 28 - 2 = 26. So there are 26 electrons in a Ni²⁺ ion.