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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Chemistry => Topic started by: luken93 on April 05, 2010, 08:14:14 pm

Title: chem help - quick q
Post by: luken93 on April 05, 2010, 08:14:14 pm: Write an overall, and ionic equation for the reaction that occurs between:
a) Magnesium Sulfate and Sodium Sulfate
Is it no reaction or am I missing something?
MgSO₄_(aq)+Na₂SO₄_(aq)->MgSO₄_(aq)+Na₂SO₄_(aq)?
Title: Re: chem help - quick q
Post by: Edmund on April 05, 2010, 09:07:29 pm: No reaction will occur
Title: Re: chem help - quick q
Post by: luken93 on April 05, 2010, 09:38:09 pm: ok thanks, got more q's though

Predict whether a reaction will occur and if so write a balanced equation

Cu+Pb(NO₃)₂
Would it be no reaction as they will both be aqueous solutions?

Mg+ZnCl₂
The answer is MgCl₂_(aq)+Zn_(s), but I'm not sure why they just "swap"
Title: Re: chem help - quick q
Post by: Edmund on April 05, 2010, 09:48:46 pm: Quote
Mg+ZnCl2
The answer is MgCl2(aq)+Zn(s), but I'm not sure why they just "swap"

That's a redox reaction

Not sure about the first though...
Title: Re: chem help - quick q
Post by: luken93 on April 05, 2010, 10:00:52 pm: Quote from: Edmund on April 05, 2010, 09:48:46 pm
Quote
Mg+ZnCl2
The answer is MgCl2(aq)+Zn(s), but I'm not sure why they just "swap"

That's a redox reaction

Not sure about the first though...
ok, so what is a redox reaction?
Title: Re: chem help - quick q
Post by: Edmund on April 05, 2010, 10:11:49 pm: Notice the oxidation numbers of Mg and Zn change.

$Mg \rightarrow Mg^{2+} + 2e^-$ oxidation number changes from 0 to +2

$Zn^{2+} +2e^- \rightarrow Zn$ oxidation number changes from +2 to 0