Making mgcl2.help please

[ChemicalReactions]

Hi,I have some mgso4, is there a way I could make mgcl2 from it? Here are my theories by using double displacement, if I add mgso4(aq) and nacl(aq) will this make sodium sulphate and mgcl2 and if it does which(if any) are solid? Also could I make it from magnesium hydroxide? 

 

Im sorry but I’m also wondering if I could make sulphuric acid from sodium or magnesium sulphate 

 

[AJ999]

Just add salt and freeze out the Na2SO4 as a hydrate!  

I have actually performed this experiment:

MgSO4 + 2 NaCl = MgCl2 + Na2SO4

After freezing to remove the Na2SO4 hydrate, the aqueous MgCl2 can be refrozen to create the interestingly clear MgCl2 crystals. Note, an excess of MgSO4 may also cause the formation of 3Na₂SO₄·MgSO₄

However, on standing in air, the crystals develop a white powder coating, so be careful on how you keep the crystals!

This technique of relying on the separation out of the Na2SO4.nH2O may work in many cases except possibly when a double salt with Na2SO4 exist or an unexpected  complex is formed (like between NH3-Na3PO4 from extra free ammonia in solution, see https://pubs.acs.org/doi/abs/10.1021/i260072a029 ).

Edited July 7, 2018 by AJ999
Added last comment