A radioactive isotope 'W' decays to 'X' which decays to 'Y' and 'Y' decays to 'Z' as represented by the figure below. What is the change in the atomic number from 'W' to 'Z'?
Correct answer: B. Decreases by 3
- A. Increases by 3
- B. Decreases by 3
- C. Increases by 5
- D. Decreases by 5
Explanation
The atomic number decreases by two during an alpha-decay and increases by 1 during beta-decay. There are two alpha decays(decreases by 4) and one beta decay(increases by 1). So the overall change is -4+1=-3(decrease by 3). It is numerical and can have only one possible answer.
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.