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October 25, 2014

October 25, 2014

Posted by **Rachel** on Friday, December 2, 2011 at 3:55pm.

at a temperature where the half-life is 21 minutes.

If the initial concentration is 8.0 mM, what would the concentration be after 46.0 minutes?

How long would it take to convert 95% of C2H6 at this temperature?

- Chemistry -
**DrBob222**, Friday, December 2, 2011 at 6:31pmFist, solve for k.

k = 0.693/t_{1/2}.

The b part of the question is solved with the following.

Set No = 8.0 mM

Solve for N. Units will be in mM.

Substitute k from the first part.

ln(No/N) = kt

For c part.

Use the same equation as part b but us No = 100

N = 5

k form part a

Solve for t.

Post your work if you get stuck.

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