Physics Unit30: Nuclear Physics and Radioactivity (id: 51d4f462c)

[单选题]
When an alpha particle is emitt5etxhyi4b 1zs9 cr6;b*s vvt 5 5nfn85p)apk ted from an unstable nucleus, the atomic mass number of nk a)pt585fpnthe nucleus

A. increases by 2.
B. decreases by 2.
C. increases by 4.
D. decreases by 4.


参考答案:  D


本题详细解析: 暂无