Chemie

ZnI     →      Ionic Bonding
  ↓                    Cations (-)
Compound        Anions (+)
  ↓
[ZnI]^- → Dissolve in H₂O → Ions disassociate (separate)

If we use electrolysis we can separate out the elements

What happens?

ZnI → Zn + I
    Simple

2ZnI → 2Zn + I₂

½ equation for e^-
Zn⁺ + e^- → Zn
I^- →  I + e^-