問題詳情
23. A rock contains 0.688 mg of 206 Pb for every 1.000 mg of 238U present. Assuming that no lead was originally present, which all the 206Pb formed over the years has remained in the rock, and that the number of nuclides in intermediate stages of decay between 238U and 206Pb is negligible, the age of the rock is calculated to be _____ years. (For 238U, t1/2 = 4.5 ×109 years.)
(A) 3.8 × 106
(B) 3.8 × 107
(C) 3.8 × 108
(D) 3.8 × 109
(E) 3.8 × 1010
參考答案
答案：D
難度：計算中-1
書單：沒有書單，新增