Question
Which of the following pairs represents isobars?
MHT CET
Chemistry
Structure of Atom
2026
MHT CET 2026 (13 April Shift 1)
MHT CET Chemistry Question (2026) — Solution
Options
- A. ^ 3 He _2 and ^ 4 He _2
- B. ^ 24 Mg _ 12 and ^ 25 Mg _ 12
- C. ^ 40 K _ 19 and ^ 40 Ca _ 20
- D. ^ 40 K _ 19 and ^ 39 K _ 19
Answer
C. ^ 40 K _ 19 and ^ 40 Ca _ 20
Step-by-step solution
Isobars are atoms of different elements having the same mass number but different atomic numbers. In the pair ^ 40 K _ 19 and ^ 40 Ca _ 20 , both have the same mass number 40 but different atomic numbers 19 and 20 respectively. Thus, they represent a pair of isobars. Answer: ^ 40 K _ 19 and ^ 40 Ca _ 20
Related: Chemistry — Structure of Atom · All PYQ Banks