Question 21
A radioactive
substance contains a number of identical nuclei that emit β-particles.
Which property of
these nuclei remains unaltered by the emission?
A charge
B neutron
number
C nucleon
number
D proton number
Reference: Past Exam Paper – June 2015 Paper 12 Q39
Solution:
Answer: C.
Beta particle is 0-1β.
The nucleon number of β-particles is zero. So, the nucleon
number of the nucleus formed is the same as the parent nucleus.
Since the β-particle has a negative charge, the
daughter nucleus will need to have a charge greater than the parent daughter so
that the charge is conserved. Similarly, it will have one more proton than the
parent nucleus.
The neutron number will
also change as the proton number has changed.
Nucleon number = Neutron
number + Proton number
No comments:
Post a Comment
If it's a past exam question, do not include links to the paper. Only the reference.
Comments will only be published after moderation