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September 18, 2014

September 18, 2014

Posted by **Val** on Sunday, March 28, 2010 at 9:00pm.

15.2 min

30.4 min

45.6 min

48.0 min

I'm not sure how to do this. I initially tried by finding k for the values given for hte half life (ln2/15.2 min=k) and hten used k to find the value for when 7/8 was left over, but I keep getting t= 2.9 minutes which isn't right.

having trouble posting so I'm doing these in parts..

- Chemistry -
**DrBob222**, Sunday, March 28, 2010 at 9:07pmk = 0.692/15.2 min

ln(No/N) = kt

I would just put in 8 for No and 1 for N --which says 7/8 is gone leaving 1/8).

ln(8/1) = kt and solve for t.

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