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Question 31.17: The value of λ for protactinium-234 is 9.63 × 10^−3 s^−1. Ta...

The value of λ for protactinium-234 is 9.63 × 10^{−3}  s^{−1}. Table 31.5 shows the number of undecayed nuclei, N, in a sample.

Copy and complete Table 31.5. Draw a graph of N against t, and use it to find the half-life t_{1/2} of protactinium-234.

t / s 0 20 40 60 80 100 120 140
N 400 330

Table 31.5 Data for Question 17

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t / s 0 20 40 60 80 100 120 140
N 400 330 272 224 185 153 126 104

Half-life is about 70 s.

31.17

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