Answer:
4 protons, 5 neutrons, 4 electrons to have the neutral Be atom
the only way to make a negative Be is to have more than 4 electrons
Explanation:
Make a neutral Beryllium atom by adding protons, neutrons and electrons. Now, what would you do to make a
beryllium atom with a negative charge?
Be has an atomic number of 4, an atomic mass 9
its atomic number tells us it has 4 protons, with a +4 charge
its atomic mass = neutrons + protons, so it has 5 neutrons with no charge
its neutral atom will have 4 electrons each with a negative charge to balance the +4 total proton harge.
so
4 protons, 5 neutrons, 4 electrons to have the neutral Be atom
to make a negative Be species, it still must have an atomic number of 4,
or it is not Beryllium
so the only way to make a negative Be is to have more than 4 electrons
