Which has the least stable configuration?
- A single atom of Chlorine
- A single atom of Argon
NaCl is an IONIC compound and readily dissociates in water But stable as the solid 'salt'
H2O is a covalent polar compound but is relatively stable
Argon is a noble gas....noble gases (neon, krypton etc) are very UN-reactive because they are stable
Clorine atoms are very reactive...chlorine is almost never found in a pure state, but rather as a compound with other elements
So I will say Chlorine atom is the least stable config.