U-235 fission representation: Which balanced representation best describes the fission of 92U235 by a slow (thermal) neutron, showing typical fission products, emitted neutrons, and released energy?

Introduction / Context:
Fission reactions are written to show target nucleus, incident neutron, fission fragments, emitted neutrons, and the energy released (Q-value). Recognizing a correct schematic equation is essential in nuclear engineering and physics.

Given Data / Assumptions:

• Thermal neutron induces fission of U-235.
• Representative fission fragments: barium-143 and krypton-90 (one of many possible splits).
• About 2–3 fast neutrons are typically emitted; 3 is a common depiction.

Concept / Approach:
The proper schematic includes the incident neutron, two fission products whose mass numbers add up with the emitted neutrons to conserve nucleon number, and the release of energy Q. Many product pairs exist; Ba-143 and Kr-90 are illustrative. The equation should include + Q (energy).

Step-by-Step Solution:
Write reaction: 92U235 + 0n1 → 56Ba143 + 36Kr90 + 3 0n1 + Q.Check mass numbers: 235 + 1 = 236 on left; right side 143 + 90 + 3*1 = 236 (balanced).Check charges: 92 = 56 + 36 (balanced).Include Q to denote energy release (~200 MeV per fission).

Verification / Alternative check:
Any valid pair of fission fragments with correct balancing and Q is acceptable; the given pair and three neutrons is standard in texts.

Why Other Options Are Wrong:
(a) Involves gamma on the reactant side and omits neutrons/Q; incorrect. (b) Omits explicit Q term. (d) Shows formation of U-236 and immediate release of 3 neutrons; this skips explicit fission fragments and is not the usual fission depiction.

Common Pitfalls:

• Forgetting to include emitted neutrons and energy term.
• Not checking mass and charge conservation.

Final Answer:
92U235 + 0n1 → 56Ba143 + 36Kr90 + 3 0n1 + Q (energy)