## Dividing Experiments to Find Order

$\frac{d[R]}{dt}=-k[R]; \ln [R]=-kt + \ln [R]_{0}; t_{\frac{1}{2}}=\frac{0.693}{k}$

Sophia Diaz - Dis 1B
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### Dividing Experiments to Find Order

I understand the process in which we find the value of n, but I don't fully understand how we determine which experiment should be divided by another. For example, the in-class example had us dividing rate 2 by rate 1, but what if we divided rate 1 by rate 2. We would no longer get 2 as an answer and instead get 1/2. So how do you know which rate to divide by in order to get the right answer?

Thanks!

Schuyler_Howell_4D
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### Re: Dividing Experiments to Find Order

Another question that goes off of this is, can you have an order be a fraction or do they have to be whole numbers?

emily gao 1C
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### Re: Dividing Experiments to Find Order

you can half fractional half reactions--> the rate law goes to a 1/2 power, etc

Ibrahim Malik 1H
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### Re: Dividing Experiments to Find Order

When solving for the reaction order, you want to try and divide the experiments as to end up with a whole number. However, ending up with fractions wouldn't necessarily make the problem wrong.

deepto_mizan1H
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### Re: Dividing Experiments to Find Order

Trying to keep it in terms of ratios can help to figure out the exponent values easier. If we need to reduce the coefficients a bit in order to do so can help as well, but in essence nothing should specifically change.