Question #b7b77

1 Answer
Dec 3, 2015

I'm not convinced that this is right in the first place. Once we see what it actually is, THAT is the empirical formula already, since we only need one #"Mg"# for the fully-reduced formula.

Notice how...

#"Mg"("ClO"_3)_2 = "MgCl"_2"O"_6#

...is NOT true. They are NOT saying the same thing at all. The former is real, and the latter cannot exist.

#"Mg"("ClO"_3)_2#, magnesium chlorate, has two chlorate (#"ClO"_3^(-)#) ions ionically bonded to magnesium, which can form a #"2+"# cation. This is probably the empirical formula if in fact this is what you were thinking of.

#"MgCl"_2"O"_6# is claiming that EIGHT atoms are connected to magnesium, which is impossible. It only has two binding sites, and many transition metals don't even have more than six binding sites. This does NOT exist.


But this is possible:

#"MgCl"_2 cdot 6"H"_2"O"#

which is magnesium chloride hexahydrate, where six waters coordinate around a previously-anhydrous #"MgCl"_2#. They aren't actually binding so that is OK.