Physics · Nuclear Physics
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If a nucleus with 198 atomic masses releases an alpha particle, its new mass becomes _____.
- A
194
- B
202
- C
200
- D
None of these
When a nucleus emits an alpha particle, these changes happen: the mass number decreases by 4, and the atomic number decreases by 2. So 198-4 gives 194.
When a nucleus emits an alpha particle, these changes happen:
The mass number decreases by 4 and the atomic number decreases by 2
So. 198-4 = 192
B suggests that the new mass of the nucleus becomes 202. However, this option is incorrect. When an alpha particle is released, the mass number of the nucleus decreases by 4. Therefore, the new mass would be lower than the original mass, not higher.
C suggests that the new mass of the nucleus becomes 200. This option is also incorrect. When an alpha particle is released, the mass number of the nucleus decreases by 4. Thus, if the original mass was 198, the new mass would be 198 minus 4 = 194, not 200.
D suggests that none of the given options are correct. While this option is technically correct, it does not provide a specific explanation.
Tagged under Physics · Nuclear Physics · 2021