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solve this problem

panthera · 2011-07-05 11:49:42

In a chemical reaction the amount of starting material (C) in cm3 left after t minutes is given by C=50e to the power of -0.005t. Determine (i) the amount of reactant present after 30minutes and (ii) the rate of change of reactant after 40 minutes I know its probably very easy but I'm stumped! I think its differentiation…

05-07-2011 11:49am

#1

panthera

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In a chemical reaction the amount of starting material (C) in cm3 left after t minutes is given by C=50e to the power of -0.005t. Determine

(i) the amount of reactant present after 30minutes and
(ii) the rate of change of reactant after 40 minutes

I know its probably very easy but I'm stumped! I think its differentiation but I'm awful at maths! Cheers.

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Comments

#2 05-07-2011 7:17pm

later12

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(i) substitute in your value of t.

(ii)are you familiar with differentiating e ?

on a very basic level, multiply the 50 in your equation by -0.005, then substitute your value for t.

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