[zakid]

Can someone provide me with some ideas on measuring the rate of reaction? I need specific examples (reaction+what to measure).

I managed to come up with this:
Na2S2O3 + HCl --> S+ SO2 + NaCl, I would measure the amount of precipitation.

[Arkcon]

Well, I'm going to give you standard mini-hint #2 -- the reaction has to be possible.  I don't think yours is.  Standard mini hint #1 is a balanced equation, and you don't really have that, but there's no point in balancing a equation that won't happen.  If you have to decide a lab practical all on your own, based on precipitation, you should be able to come up with another one.

Gah.  I misread your formula.  You should balance it first, anyway.

[Borek]

No hydrogen on the RHS

[zakid]

Forgot to add H2O
This should be balanced correctly:
Na2S2O3 + 2HCl --> SO2(g) + S(s) + H2O(l) + 2NaCl(aq)

Anyway, can you come up with some other examples?