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  9. Q9

PPSC PCS 2015 · Question 9 of 100

1H3 and2He4 are

Science & Tech

  1. ANuclear isomers
  2. BIsotonesCorrect
  3. CIsodiaphers
  4. DIsobars

Answer: B. Isotones

Explanation

Tritium (1 proton, 2 neutrons) and Helium-4 (2 protons, 2 neutrons) have the same neutron number, making them isotones.

Source: https://cdn.mindspritesolutions.com/examrace/SPSC/Punjab-PSC/Punjab-PSC-Past-Papers/Punjab-Civil-Service-2015-Official-Paper-1-Part-1.pdf

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