Question

What is the proper name for MgF₂?

A) Magnesium fluoride

B) Magnesium (I) fluoride

C) Magnesium (II) fluoride

D) Magnesium difluoride

My answer key says the answer is A) Magnesium Fluoride but I thought the answer was D) Magnesium difluoride since there are 2 fluorides. Please help me out and explain. Thanks! :)

Answer 1

MgF2

we can see that

the oxidation number of Mg is +2

and

oxidation number of F is -1

so

there is a possibility to write it as

Magnesium (II) fluoride

but the rule is that

the charge number should be only used in case of transition metals

but Mg is not a transition metal

So the charge number should not be mentioned

so

option B and C are eliminated

finally

the term difluoride is used only when flourine binds with a non metal

but

magnesium is a metal

so

the term difluoride should not be used

so

the answer is

A) magnesium flouride