During radioactive decay of a nucleus zXA, β emission takes place along with the daughter nucleus. Because of this beta particle emission, the mass number (A) of the parent nucleus:
Correct answer: A. Remains constant
- A. Remains constant
- B. Decreases by 1
- C. Increases by 1
- D. Decreases by 2
Explanation
On emitting a β particle the number of nucleons in the nucleus (i.e. protons and neutrons) remains same, but the number of neutrons is decreased by one and the number of protons is increased by one. If a radioactive nucleus P with mass number A and atomic number Z emits a beta particle to form a daughter nucleus Q with mass number A and atomic number Z+1. (a) Atomic number Z is not conserved. It is increased by 1. (b) Mass number A is conserved. Result: So, from the above discussion it is clear thwt mass number (A) remains constant after the beta decay and not increased or decreased .
Last updated
About Nuclear Physics
Atomic nuclei contain protons and neutrons, with nuclear size, mass defect and binding energy describing their stability. The work covers alpha, beta and gamma decay, decay equations, half-life and decay rate, along with radiation safety and medical applications such as imaging, radiotherapy and tracers.
Practise Nuclear Physics
1,254 free Nuclear Physics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.