Practice portal › Nuclei › Nuclear Reactions, Fission and Fusion

²⁹⁰₈₂X α Y e⁺ Z β⁻ P e⁻ Q
In the nuclear emission stated above, the mass number and atomic number of the product Q respectively, are

Asked in NEET 2024 · Q-value, decay and conservation laws

• (1) 288, 82
• (2) 286, 81
• (3) 280, 81
• (4) 286, 80

Step-by-step solution

Why the other options are wrong

• (1) No single slip gives 288, 82: it would need the α particle to carry off only two nucleons and the four emissions to leave the charge where it started.
• (3) Comes from taking 2 off the mass number for each of the three electron-type emissions as well as 4 for the α (290-4-6=280); an electron or a positron carries no nucleons.
• (4) Stops one step early: 286, 80 is the nucleus P. Emitting the last electron raises the atomic number to 81.

Reading this solution needs no sign-in. You only sign in to practise against the clock and keep your progress.