# Question

Nuclide A has a decay constant that is half that of nuclide B. Samples of both types start with the same number of undecayed nuclei, N. In terms of N, after two of A’s half-lives have elapsed,

(a) How many of type A have decayed?

(b) How many of type B have decayed?

(a) How many of type A have decayed?

(b) How many of type B have decayed?

## Answer to relevant Questions

What are the (a) Half-life (b) Decay constant for a stable isotope? Explain how the fusing of very light nuclei and the split-ting of very heavy nuclei can both release energy. Determine the number of protons, neutrons, and electrons in a neutral atom with the following nuclei: (a) 90Zr and (b) 208Pb. The decay series for neptunium-237 is shown in Fig. 29.20. (a) What is the decay mode of each of the sequential decays? (b) Determine the daughter nucleus at the end of each decay. Prove that the number N of radioactive nuclei remaining in a sample after an integer number (n) of half-lives has elapsed is N –No/2n = (1/2)n No. Here No stands for the initial number of nuclei.Post your question

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