Which of the following pairs are isobars? MCQ with Answer and Explanation

Which of the following pairs are isobars?
A. ¹H and ²H
B. ³⁵Cl and ³⁷Cl
C. ⁴⁰Ar and ⁴⁰Ca
D. ¹²C and ¹⁴C
Answer: Option C
Solution (By JKSSB Mock Tests)
Isobars are atoms of different elements with the same mass number but different atomic numbers. ⁴⁰Ar (atomic number 18) and ⁴⁰Ca (atomic number 20) both have mass number 40. Options A and D are isotopes (same element, different mass number). Option C are isotopes of hydrogen. Isobars have different chemical properties because of different proton numbers. Example: ¹⁴C and ¹⁴N.

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Correct Answer: Option C


Explanation:
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Correct Answer: Option D


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Question #3
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Correct Answer: Option A


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