Calculate Decay Constant of Sodium Isotope: 2.6 Years Half Life

AI Thread Summary
The discussion focuses on calculating the decay constant for a sodium isotope with a half-life of 2.6 years. The formula used is T = ln(2) / λ, where T is the half-life and λ is the decay constant. A participant initially struggled with the conversion of years to seconds but ultimately corrected their mistake by properly calculating the total seconds in 2.6 years. The correct decay constant is confirmed to be 8.4 x 10^-9 s^-1. The conversation highlights the importance of accurate unit conversion in such calculations.
benhorris
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Simple question, but i don't know where to start.

The half life of one radioactive isotope of sodium is 2.6 years. Show that its decay constant is 8.4 x 10^-9 s^-1.

Thanks in advance,

Ben.
 
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T_h = \frac {ln2} { \lambda}



But remember to convert the time into seconds!
 
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Do you know the following identity T = \frac{ln 2}{\lambda}, where T is the half life in seconds and \lambda is the decay constant.
 
Ah got it,

Thanks guys.

Was a simple error, i converted it to seconds by doing =

2.6 x 365 x 3600. And i forgot about the hours.

3600 x 24 x 365 x 2.6 = no.seconds gave the correct answer.

Silly mistake.
 
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