10. (a) r155luue(uilu IIIII I'v'----vr~r. a ,' ' The end product of the uranium disintegration series is (a) lead; (b) zinc; (c) carbon; (d) tin. (a) Name the elements with longest half lives of the each series. Ul(4.5 x 1010 yr); 7110.41 x 10'0 yr); AcU(7.l x 103 yr); Np(2.2 x 106 yr) Which one of the following is incorrect? The decay constant 1 is (a) the important character of each radioactive nuclide; (1)} independent 0f physical character and chemical conditions; (c) independent of the age of that nuclide, ((1) None of these. (:1) If no more 14C of half life of 5500 yr enters biological systems after their death, estimate the age of the remains of a tree whose radioactivity is 1/4 of that of a comparable but relatively young tree. [11000 yr] Radiocarbon dating is used to (a) treat a disease by means of radiation: (b) study and apply chemical techniques to the purication of radioactive materials; (c) estimate the age of wooden archaeological objects; (d) all of these. (c) - - .. =- "mum: r." at Uranium dating; (b) radiocarbon dating: (c) atomic clocks; (d) biological