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MHT CET Medical202624 April 2026Evening ShiftChemistryStructure of AtomActual

Identify the pair of atoms of elements as isotones from the following.

Options

  1. A₆ C ¹² , ₆ C ¹⁴
  2. B₆ C ¹⁴ , ₇ N ¹⁴
  3. C₅ B ¹¹ , ₆ C ¹²
  4. D₇ N ¹⁴ , ₈ O ¹⁶

Correct answer

C. ₅ B ¹¹ , ₆ C ¹²

Step-by-step solution

Isotones are atoms of different elements having the same number of neutrons. The number of neutrons is given by A - Z , where A is the mass number and Z is the atomic number. For ₅ B ¹¹ , number of neutrons = 11 - 5 = 6 For ₆ C ¹² , number of neutrons = 12 - 6 = 6 Since both have the same number of neutrons, they are isotones. Answer: ₅ B ¹¹ , ₆ C ¹²

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