Solved UPSC CDS/OTA Question
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Q · Structure of the AtomMedium · 45s
Consider the following statements: 1. Isotopes have the same atomic number but different mass numbers. 2. Isobars have different atomic numbers but the same mass number. Which of the above is/are correct?
TopicStructure of the Atom
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Isotopes: Same Z, different A. Isobars: Different Z, same A.
Final Answer: Option C — Both 1 and 2