Step-by-step explanation:
Ionic compounds are compounds formed by the bonding of a metal with a non metal.
A. NO2
This is not an ionic compound because N and O are non metals.
B. CaCl2
This is an ionic compound because Ca is a metal and Cl is a non metal.
C. KI
This is an ionic compound because K is a metal and I is a non metal.
D. CO2
This is not an ionic compound because C and O are non metals.
E. H2O
This is not an ionic compound because H and O are non metals.
F. NaCl
This is an ionic compound because Na is a metal and Cl is a non metal.