Why the sodium chloride is named as NACL?

Answer 1

In the case of NaCl.the valency of sodium and chloride is two.so you dont have to specify it.but where as in Icl the valency different so you call it as iodine monochloride.to denote the presence of single chloride atom.

Sodium chloride is an ionic compound, so you don't write 'mono' 'di' 'tri' etc. in the name. MgCl2 would simply be magnesium chloride, not magnesium dichloride. Covalent compounds such as ICl sometimes have 'mono' 'di' or 'tri' in their name, but ionic compounds don't.

== == == == == ==

Answer 2

I think that's because that is it's Latin name like loads of the elements of the Periodic Table have Latin names like gold is Au.