The number of protons is 12, the number of electrons is 10, the number of neutrons is different for each isotope.
There are 1.20 equivalents in 0.60 mole of Mg2+, since Mg2+ has a charge of 2+.
Mg2+: [1s22s22p6]
Magnesium, ion (Mg2+)
The electron configuration for a magnesium cation Mg2 plus is 1s2.2s2.2p6.
An Mg2+ ion has lost two electrons, resulting in a total of 10 electrons. Magnesium normally has 12 electrons but when it forms a 2+ ion, it loses two electrons.
There are 10 electrons in Mg2+ because the atomic number of magnesium is 12, which means it normally has 12 electrons. When it forms a 2+ ion, it loses 2 electrons, leaving 10 electrons in the Mg2+ ion.
Mg2+
Cu + Mg2 --------> Cu2 + Mg Cu --------------> Cu2 + 2e Mg2 + 2e --------> Mg Cu --------------> Cu2 + 2e (E = +0.35) Mg2 + 2e --------> Mg (E = -2.36V) +0.35 + (-2.36) = -2.01V --------------------------------------… Mg + Cu2 --------> Mg2 + Cu Mg --------------> Mg2 + 2e Cu2 + 2e --------> Cu Mg --------------> Mg2 + 2e (E = +2.36V) Cu2 + 2e --------> Mg (E = -0.35V) +2.36 + (-0.35) = +2.01V
Magnesium that has lost 2 electrons.
The number of protons is 2.
NO3-
Mg has 12 protons, 12 electrons and 12 neutrons.Mg^2+ ion has 12 protons, 10 electrons and 12 neutrons. The number of protons and neutrons remains the same, but since the ion now has a 2+ charge, it has lost 2 electrons.