Question

The correct statement of the following is

• A. The \(Q\)-value of a nuclear process is the difference between final and initial kinetic energies.
• B. The nuclear mass is always higher than the total mass of its constituents.
• C. Nuclides with same number of neutrons in the nucleus are known as isotopes.
• D. In nuclear fusion, a heavy nucleus breaks into two smaller fragments.

Hint:

Remember: \[ Q=K_f-K_i \] for nuclear reactions. Also,

• Isotopes \(\rightarrow\) same atomic number.

• Isotones \(\rightarrow\) same number of neutrons.

• Fission \(\rightarrow\) heavy nucleus splits.

• Fusion \(\rightarrow\) light nuclei combine.

Answer 1

The Correct Option is A

Step 1: Check each statement for correctness.
Statement 1: Q-value = \( K_f - K_i \) (final minus initial kinetic energy). Correct by definition from mass-energy equivalence. Statement 2: Nuclear mass is always LESS than total free nucleon mass (mass defect). False. Statement 3: Same neutron number = isotones, not isotopes. False. Statement 4: Fusion combines light nuclei; fission breaks heavy ones. Statement 4 is false.

Step 2: Select the true statement.
\[ \boxed{\text{The Q-value of a nuclear process is the difference between final and initial kinetic energies.}} \]