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### Topic: Quick quick quick help needed with finding the percent difference of these 2?  (Read 1163 times)

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#### webassignbuddy

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##### Quick quick quick help needed with finding the percent difference of these 2?
« on: September 12, 2013, 09:24:14 PM »
Problem:

Tables Needed:

My calculations:

% difference for absorbance (SOLID) = [(0.336 theoretical - 0.385 nm actual) x 100%]/0.336 theoretical
% difference for absorbance (SOLID) = (-0.049 x 1)/0.336 theoretical
% difference for absorbance (SOLID) = -0.146 (INCORRECT - 2/3 submissions)

% difference for absorbance (STOCK SOLUTION) = [(0.336 theoretical unknown - 0.962 nm actual) x 100%]/0.336 theoretical
% difference for absorbance (STOCK SOLUTION) = (-0.626 x 1)/0.336 theoretical
% difference for absorbance (STOCK SOLUTION) = -1.86 (INCORRECT 3/3 submissions)

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% difference for concentration M (SOLID) = (0.102 M theoretical - 0.117 M actual)/0.102
% difference for concentration M (SOLID) = -0.015/0.102
% difference for concentration M (SOLID) = -0.147 (INCORRECT - 1/3 submissions)

% difference for concentration M (STOCK SOLUTION) = (0.102 M theoretical - 0.304 M actual)/0.102
% difference for concentration M (STOCK SOLUTION) = -0.202/0.102
% difference for concentration M (STOCK SOLUTION) = -1.98 (INCORRECT - 1/3 submissions)

The values in blue were taken from my 2 In-Lab tables but for some reason, webassign is marking all of them as wrong!

#### Borek

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##### Re: Quick quick quick help needed with finding the percent difference of these 2?
« Reply #1 on: September 13, 2013, 02:40:01 AM »
% difference for absorbance (SOLID) = -0.146 (INCORRECT - 2/3 submissions)

And not -14.6%?
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