How do you name #MgCl_2#?

1 Answer
Jul 8, 2016

Magnesium chloride


Magnesium is in group II and will always form a 2+ ion when reacting. Equally, chorine is I group VII and will tend to gain one electron from a metal to form a 1- ion. #MgCl_"2"# is therefore the only possible formula for magnesium chloride.

Compare this to iron chloride. Iron can form a 2+ or 3+ ion, therefore you must make a difference in naming #FeCl_2=# iron(II) chloride and #FeCl_3=# iron(III) chloride.