Answer is: 2. can dissolve.
Ionic compounds separates into particles (ions) in water because of their ionic bond.
For example sodium chloride is ionic compound and strong electrolyte and dissociates in water on hydrated sodium cations and chlorine anions:
NaCl(aq) → Na⁺(aq) + Cl⁻(aq).
Ionic bond is the electrostatic attraction between oppositely charged ions (cations and anions).
Only one atom because atom with 17 electrons need that one electron to become stable
This is easy… like you can’t take 20 min to search this up in Googl
