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help with preperation of salts question

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june:
I have no idea how these type of questions that come up in paper 6 are to be answered! could anyone please explain? I have the answer but i dont know why it is that answer..
November 2008 paper 6..
Page11 Q7..
A solution of magnesium sulphate can be made by reacting magnesium oxide with warm sulphuric acid.
a) Describe how you could make a solution of magnesium sulphate starting with magnesium oxide powder and dilute sulphuric acid.
b) Describe how you would obtain pure dry crystals of hydrated magnesium sulphate, MgSO4.7H2O from the solution of magnesium sulphate in (a).
Thank you!

sweetsh:
Okay..What I took with my GREAT teacher  8) God bless him for me  :P
The following.
Magnesium sulphate is a soluble salt so I think we should use Mg(OH)2 (Magnesium hydroxide) not MgO ...
1)So we make titration to Mg(OH)2 with H2SO4 using an indicator..
H2SO4+Mg(OH)2 --> MgSo4 +H2O
2)repeat titration without indicator
3)heat till saturation
4)make crystillization (cooling,filtering,wash crystals with small amount of water)

SGVaibhav:
i never understood why wash crystals. (i neveer did that too while making crystals)

emi:

--- Quote ---1)So we make titration to Mg(OH)2 with HCl using an indicator..
HCl+Mg(OH)2 --> MgSo4 +H2O
--- End quote ---

you mean with H2SO4 not HCL ??

sweetsh:
Sorry H2SO4
I was confused I was fighting with someone while writing this sorry guys  :)

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