Determine the activity of 6.0 × 10¹² atoms of Rn-220 that has a half-life of 56 s. A)2.0 Ci B)2.5 Ci C)3.0 Ci D)3.5 Ci E)4.0 Ci

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The activity of a radioactive sample is given by the equation:$$A = -\frac{dN}{dt} = \lambda N$$where:* A is the activity in becquerels (Bq)* N is the number of radioactive atoms* λ is the decay constant in s^-1The decay constant is related to the half-life (t_1/2) by the equation:$$\lambda = \frac{ln 2}{t_{1/2}}$$Substituting the given values into these equations, we get:$$\lambda = \frac{ln 2}{56 s} = 0.0124 s^{-1}$$$$A = (0.0124 s^{-1})(6.0 × 10^{12} atoms) = 7.44 × 10^{10} Bq$$Converting to curies (Ci), we get:$$A = (7.44 × 10^{10} Bq) \left(\frac{1 Ci}{3.7 × 10^{10} Bq}\right) = 2.01 Ci$$Therefore, the activity of the sample is 2.01 Ci, which is closest to choice A) 2.0 Ci.

Determine the Activity of 6