Sau 3 phân rã \(\alpha\) và 2 phân rã \(\beta ^{-}\), hạt \(_{92}^{238}\textrm{U}\) biến đổi thành hạt nhân
A.\(_{90}^{230}\textrm{Th}\)
B. \(_{91}^{226}\textrm{Pa}\)
C. \(_{90}^{226}\textrm{Th}\)
D.\(_{88}^{226}\textrm{Ra}\)
A.\(_{90}^{230}\textrm{Th}\)
B. \(_{91}^{226}\textrm{Pa}\)
C. \(_{90}^{226}\textrm{Th}\)
D.\(_{88}^{226}\textrm{Ra}\)
Hướng dẫn
\(_{92}^{238}\textrm{U}\rightarrow 3_{2}^{4}\textrm{He}+2_{-1}^{0}\textrm{e}+_{Z}^{A}\textrm{X}\)
\(\Rightarrow \left\{\begin{matrix} 238=3.4+2.0+A\\92=3.2+2.(-1)+Z \end{matrix}\right.\Rightarrow \left\{\begin{matrix} A=226\\Z=88 \end{matrix}\right.\)
\(\Rightarrow _{88}^{226}\textrm{Ra}\)
\(_{92}^{238}\textrm{U}\rightarrow 3_{2}^{4}\textrm{He}+2_{-1}^{0}\textrm{e}+_{Z}^{A}\textrm{X}\)
\(\Rightarrow \left\{\begin{matrix} 238=3.4+2.0+A\\92=3.2+2.(-1)+Z \end{matrix}\right.\Rightarrow \left\{\begin{matrix} A=226\\Z=88 \end{matrix}\right.\)
\(\Rightarrow _{88}^{226}\textrm{Ra}\)
Nguồn: Học Lớp