15.19

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Sohini Halder 1G
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Joined: Thu Jul 13, 2017 3:00 am
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15.19

Postby Sohini Halder 1G » Wed Feb 28, 2018 12:11 pm

I am confused about 15.19. When I find k, I get 2.85 x 10-^12 mol/Ls. The answer key gives the same value but as mmol/Ls. This is wrong right? We have to convert the mmol to mol to get a power of 10^-12, but why is the units for the answer key still mmol/Ls?

Cooper1C
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

Re: 15.19

Postby Cooper1C » Wed Feb 28, 2018 2:13 pm

From experiment 2:

17.4 mmol/L*s = k(2.5 mmol/L)(1.25^2 mmol^2/L^2)(1.25^2 mmol^2/L^2)
k = 17.4 mmol/L*s /(1.25^2*1.25^2*2.5) mmol^5/L^5

The mmol and L cancel, so you have

k = 17.4/s /(1.25^2*1.25^2*2.5) L^4/mmol^4

1 mmol = 10^3 mol, so

k = 17.4/(1.25^2*1.25^2*2.5)* 10^12 L^4/mol^4*s

Sue Xu 2K
Posts: 58
Joined: Fri Sep 29, 2017 7:06 am

Re: 15.19

Postby Sue Xu 2K » Wed Feb 28, 2018 3:58 pm

I have the same question. I think the answer key is wrong. It should either be 2.85 x 10-^12 mol/Ls or 2.85 mmol/Ls.


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