If the nucleons of a nucleus are separated from each other, the mass is increased. Where does this mass come from?

Suppose we have 12 protons and 12 neutrons. We can assemble them to form either a ²⁴Mg nucleus or two ¹²C nuclei. In which of the two cases more energy will be liberated?

What is the difference between cathode rays and beta rays? When the two are travelling in space, can you make out which is the cathode ray and which is the beta ray?

In beta decay, an electron (or a positron) is emitted by a nucleus. Does the remaining atom gets oppositely charged?

When a boron nucleus (¹⁰B) is bombarded by a neutron, an α-particle is emitted. Which nucleus will be formed as a result?