Physics Nuclear Physics DUHS 2022
PMDC Verified Question 44 of 98
In nuclear reaction \( _7\text{N}^{14} + _2\text{He}^4 \rightarrow _8\text{O}^{17} + \_\_\_\_ \), the missing particle is:
A
Proton
B
\(\alpha\)-particle
C
Electron
D
Positron
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: Proton


Concept:

In any nuclear reaction, the sum of mass numbers (superscripts) and atomic numbers (subscripts) must be completely conserved on both sides.

Solution:

  • Left Side (Reactants):
    Total Mass (A) = \( 14 + 4 = 18 \)
    Total Charge (Z) = \( 7 + 2 = 9 \)


  • Right Side (Products):
    Current Mass (A) = \( 17 + A_x \)
    Current Charge (Z) = \( 8 + Z_x \)


  • Balance:
    \( 18 = 17 + A_x \implies A_x = 1 \)
    \( 9 = 8 + Z_x \implies Z_x = 1 \)


  • The particle with Mass = 1 and Charge = 1 is \( _1^1\text{H} \), which is a Proton.


Why other options are incorrect:

An alpha particle is (4,2). An electron is (0,-1). A positron is (0,+1). None balance the equation.

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Nuclear Physics MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App