Question

Why does beryllium have 4 neutrons

Answer 1

Beryllium has an atomic number of 4, which means it has 4 protons in its nucleus. In order to be a neutral atom, it also needs to have 4 electrons. Neutrons help stabilize the nucleus of an atom by providing additional nuclear binding energy. In the case of beryllium, having 4 neutrons helps to balance the repulsive forces between the positively charged protons in the nucleus.