The radioactive nucleus undergoes a series of decay according to the scheme (given below). If the mass number and atomic number of A are 180 and 72 respectively, then what are these number for A4.
Correct answer: A. 172 and 69
- A. 172 and 69
- B. 172 and 70
- C. 174 and 70
- D. 176 and 70
Explanation
To summarise, in alpha decay, the atomic number decreases by 2 and the mass number decreases by 4 due to the emission of an alpha particle. In beta-minus decay, the atomic number increases by 1 while the mass number remains the same due to the emission of an electron. In beta-plus decay, the atomic number decreases by 1 while the mass number stays constant due to the emission of a positron. In gamma decay, there are no changes in atomic number or mass number; it involves the emission of high-energy electromagnetic radiation, making option A correct.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
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.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Nuclear Physics questions
Radon-220 is radioactive and decays to polonium-216 with the emission of an α-particle. The equation for the radioactive decay is shown.86220Rn→84216Po+24 .He how many neutrons are in the radon and polonium nuclei?
The order of penetration power of α and β and ϒ-rays is
α β and ϒ are emited from a radioactive substance
The masses of two radioactive substances are same and thier half-lives are 1 year and 2 years respectively. The ratio of their activities after six year will be:
Let T be the mean life of a radioactive sample. 75% of the active nuclie present in the sample initially will decay in time.
In a sample of radioactive material, what fraction of the initial number of active nuclei will remain undisintegrated after half-life of the sample?