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1. There was this question that asked me to work out the decay constant of a subtance which has a half life of 2.6 years. I used the equation k=In2/Half life

The question also gave me the information that 1 year is equal to 3.15 * 10^7 seconds. I basically set the equation out like this:

k = In2/ 2.6 * 3.15 * 10^7

According to the mark scheme this was supposed to be the correct way to set out the answer and for it the value of k (the decay constant) came to 0.46 * 10^-9 . Now, the mark scheme stated that the correct answer should be 8.6 * 10^-9 . So now I'm wondering is the mark scheme wrong or is it possible that the fault lies rather in my calculator.
2. Hm. I got 8.5 * 10^-9 when I did it.

Have you checked it and made sure you'd got brackets in the right place and everything?

Edit: Sorry, did you mean 0.46 or 8.46? 'Cause if you mean the latter I got the same.

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Updated: June 9, 2008
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