(a) The half-life of radium-226 is 1620 years. Write a formula for the quantity, Q, of radium left after t years, if the initial quantity is Q(adsbygoogle = window.adsbygoogle || []).push({}); _{0}.

Check me on this one:

Q = (Q_{0}/ 2^{(1620/t)})

(b) What percentage of the original amount of radium is left after 500 years?

Check this one as well:

Q = (Q_{0}/ 2^{1620/500})

Q = (Q_{0}/ 2^{3.24})

Q = Q_{0}* 2^{-3.24}

Q = Q_{0}(0.1058)

10.6%

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# Homework Help: Half-life and decay

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