Two different atoms have four protons each and the same mass. However, one has a positive charge while the other is neutral. Describe what each atomic structure could be, listing the possible number and location of all subatomic particles.

Below.

Explanation:

The neutral atom which had 4 protons in the nucleus is beryllium (Be) with atomic structure 1s^2s^2.

It has 4 electrons, the 2 s^2 are valency electrons, and the main isotope has 5 neutrons to give a mass number of 9.

When combining with other elements, for example chlorine, to form the salt BeCl2 the Be forms the Be2+ ion ( positive charge of 2).

The atomic structure will be the same as for that of Be except that there will only be 2 electrons, the 1s^2 electrons.