Nuclear fusion & nuclear fission answers
(b) t½ = (ln 2) / λ = 0.693 / λ so λ = 0.693 ÷ 23.5 = 0.0295 min-1 N = Noe−λt so N / No = e−(0.0295 x 141) = 0.0156 Percentage remaining = (N / No) x 100 = 1.56%. This can more easily be solved by inspection. 141 minutes is equal to 6 half-lives. 1 ⟶ 0.5 ⟶ 0.25 ⟶ 0.125 ⟶ 0.0625 ⟶ 0.03125 ⟶ 0.0156 (i.e. 1.56 %) (c) Three neutrons produced since: 2. Each element has its own specific absorption spectrum (the opposite to...