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A Level Chemistry Initial Rates method vs Continuous Monitoring

Can you use the initial rates method (eg clock reaction) and a continuous monitoring method interchangeably or is one method better than another in specific types of reactions? If so, when would each be preferred? Thanks
I think that each method works better for separate reactions/practicals.

Initial rates is better for measuring how concentration affects rate - Iodine clock reaction is a good example (Practical 7a for AQA)
Continuous monitoring is seeing how concentration/rate changes over time - the reaction between Mg and HCl is good (Practical 7b for AQA)

Hope that makes sense!
Original post by emrex03
I think that each method works better for separate reactions/practicals.

Initial rates is better for measuring how concentration affects rate - Iodine clock reaction is a good example (Practical 7a for AQA)
Continuous monitoring is seeing how concentration/rate changes over time - the reaction between Mg and HCl is good (Practical 7b for AQA)

Hope that makes sense!


Thank you!! I do get that, but I’m wondering why the continuous monitoring method is a better choice for the HCl and Mg reaction, as opposed to the initial rates? Like is there a specific fact about the reaction that makes it suitable
Original post by fluffypoopies
Thank you!! I do get that, but I’m wondering why the continuous monitoring method is a better choice for the HCl and Mg reaction, as opposed to the initial rates? Like is there a specific fact about the reaction that makes it suitable

Iodine clock type reactions do not actually measure the initial rate, they measure the average rate over that specific time span. Initial rate methods measure the gradient to the curve at t=0.

The initial rate is the fastest rate of the reaction, which then decreases in a non-linear fashion.

Clock type reactions give the average rate, which of course has slightly different parameters as the time taken changes.
Original post by charco
Iodine clock type reactions do not actually measure the initial rate, they measure the average rate over that specific time span. Initial rate methods measure the gradient to the curve at t=0.

The initial rate is the fastest rate of the reaction, which then decreases in a non-linear fashion.

Clock type reactions give the average rate, which of course has slightly different parameters as the time taken changes.

OCR A call clock methods by the name initial rates method.

Don't get me started.

Oh, you just did.
Original post by Pigster
OCR A call clock methods by the name initial rates method.

Don't get me started.

Oh, you just did.

sigh ...

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