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scoundrel [369]
4 years ago
9

The half-life of Actinium 227 decays in 20 years. Calculate the mass of the element left when a 2kg sample was left for 160 year

s.
Physics
1 answer:
nataly862011 [7]4 years ago
3 0

The mass of Actinium 227 left is 0.0078 kg

Explanation:

The amount of mass left of a radioactive isotope after time t is given by the equation:

m(t) = m_0 (\frac{1}{2})^{-\frac{t}{\tau_{1/2}}}

where

m_0 is the initial amount of the sample

t is the time

\tau_{\frac{1}{2}} is the half-life of the isotope

For the sample of Actinium 227 in this problem,

m_0 = 2 kg

\tau_{1/2}=20 years

t = 160 years

Substituting into the equation,

m(160) = (2 kg) (\frac{1}{2})^{-\frac{160}{20}}=0.0078 kg

#LearnwithBrainly

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