Question

how does an atom change if all of its electrons are removed?
the atoms volume increases.
the atoms mass increases.
the atom becomes positively charged.
the atom becomes negatively charged.

Explanation:

An atom is neutral with equal number of protons (positively - charged) and electrons (negatively - charged). When all electrons are removed, only positively - charged protons remain, making the atom positively charged. The mass of electrons is negligible compared to protons and neutrons, so mass doesn't increase significantly. The volume of an atom is mainly due to the electron cloud, so volume decreases when electrons are removed.

Answer:

The atom becomes positively charged.