Question

If uranium (mass number 238 and atomic number 92) emits an α-particle, the product has mass no. and atomic no.
(a) 236 and 92
(b) 234 and 90
(c) 238 and 90
(d) 236 and 90

Answer 1

answer will be b) 234 and 90..

Answer 2

Answer:

Explanation:

The nuclear disintegration process emitting alpha particles is called as the alpha decay. If the α-particle is emitted, the two equations will be -

= 92U238 →→ 90Th234+2He4

In this nuclear change, the uranium atom (U92238) transmuted into an atom of thorium (Th90,234) and, in the process, gave off an alpha particle. The bottom number in the nuclear symbol represents the number of protons. This means that the alpha particle consists of two protons in it that were lost by the uranium atom. Thus -

90Th234 →→ 92U234+ 2β

Thus the atomic number of final nucleus will be 92 and the mass number will be 234.