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Chem4 Rate equations question? watch

1. The reaction in part a was repeated at the same temp but water was added so that the volume of the reaction mixture was doubled.
Calculate initial rate under these conditions?

So using a known rate from before, how do you know by what factor the rate changes due to change in volume of the reaction mixture?
2. (Original post by bobwibbles)
The reaction in part a as repeated at the same temp but water was added so that the volume of the reaction mixture was doubled.
Calculate initial rate under these conditions?

So using a known rate from before, how do you know by what factor the rate changes due to change in volume of the reaction mixture?
Well.. that depends on the rate order of the reagent, and of how many reagents there are in the reaction...

If you double the volume of the reaction mixture, what are you doing to the concentration?
You're essentially halving the concentration. And you're halving the concentration of ALL the substances,

Now, you can figure out what effect halving this concentration has on the rate, depending on which order of kinetics the reagent follows (e.g. first order, second order)
3. (Original post by telepathicnine)
Well.. that depends on the rate order of the reagent, and of how many reagents there are in the reaction...

If you double the volume of the reaction mixture, what are you doing to the concentration?
You're essentially halving the concentration. And you're halving the concentration of ALL the substances,

Now, you can figure out what effect halving this concentration has on the rate, depending on which order of kinetics the reagent follows (e.g. first order, second order)
I understand now so you sub in 0.5 into rate equation before each reactant and then work out rate whilst considering the order of each reactant.
Makes sense.

thank you.

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