K(Potassium) and Na(Sodium) are the two most reactive metals. K’ and Na‘ are electronic structures as they have one valence electron.
where ‘F’ is a halogen
Four physical properties of the compounds formed by these elements and halogens are:
(i) They have high melting point.
(ii)They are soluble in water.
(iii) They conduct electricity in molten state not in solid state.
(iv) They are solid and somewhat hard.