The atomic number gives the number of protons OR the number of electrons in an atom (the number of protons and the number of electrons are always the same for the NEUTRAL atom).
The mass number give the sum of the number of protons plus the number of neutrons.
The charge on an ion gives you the number of excess electrons on the atom (to make the ion) and it will be negative if there are an excess of electrons (more electrons than protons) and positive if there are more protons than electrons.
the atomic number of oxygen is 8. How many protons, neutrons and electrons are in an oxygen icon with a charge of -2 and a mass number of 17?
1 answer
1 answer