Question

Years Element A Element B Element Element D 0 100 100 100 100 50 1000 2000 3000 4000 5000 6000 53 48 2 1 7000 8000 43 0 9000 390 10000 11000 12000 13000 14000 15000 16000 17000 18000 19000 20000

A) According to the data, what are the approximate half-lives of the hypothetical elements A, B, C, and D?

B) Which of the hypothetical substances would be the most harmful to living organisms? Why?

C) What part of an original isotope's number of atoms remains after two half-lives?

D) After three half-lives of an isotope, 1 billion (one-eighth) of the original isotope's atoms still remain in a certain amount of this element. How many atoms of the daughter product would you expect to be present?

E) By measuring the amounts of parent isotope and daughter product in the materials contained in a rock, and by knowing the half-life of the parent isotope, a geologist can calculate the absolute age of the rock. A rock contains 125 g of a radioisotope with a half-life of 150,000 years and 975 g of its daughter product. How old is the rock according to the radiometric dating method?

Answer 1

solution at t= t1/2 N=N/2 (til2) A = 4000 years (t1/2)3 = 13000 years {"l2) c = 6500 years 1t112) = 1000 years. I D' is most harmful as its radiating maximum. # After two half life it will remain 25% # It will form 7/8 times of nuclei 3