Which of the following is (n, p) type reaction? — Nuclear Chemistry and Radioactivity Chemistry Question

💡 Solution & Explanation

Step 1 - Definition of (n, p) Reaction An **(n, p)** reaction means: a **neutron** (n) is the projectile (absorbed) and a **proton** (p) is the ejectile (emitted). The general form is: $$\text{Target} + \ce{^1_0n} \to \text{Product} + \ce{^1_1H}$$ Note: $Z$ decreases by 1, $A$ stays the same. Step 2 - Check Each Option **(A) $\ce{^{13}_5C + ^1_1H -> ^{14}_6C}$**: Projectile is $p$, ejectile is $\gamma$ → this is a **(p, γ)** reaction. Incorrect. **(B) $\ce{^{14}_7N + ^1_1H -> ^{15}_8O}$**: Projectile is $p$, ejectile is $\gamma$ → **(p, γ)** reaction. Incorrect. **(C) $\ce{^{27}_{13}Al + ^1_0n -> ^{27}_{12}Mg + ^1_1H}$**: Check: $Z: 13+0=13 = 12+1\ \checkmark \quad A: 27+1=28=27+1\ \checkmark$ Projectile is neutron, ejectile is proton → This is an **(n, p)** reaction. **Correct.** **(D) $\ce{^{235}_{92}U + ^1_0n -> ^{140}_{54}Xe + ^{94}_{38}Sr}$**: Neutron is absorbed and multiple neutrons and fragments are produced → this is **nuclear fission**, not a simple (n, p) reaction. Incorrect. $$\boxed{\text{Answer: C — Al-27(n, p)Mg-27 is an (n, p) type reaction}}$$