Chemistry Equilibrium PMC 2021
PMDC Verified Question 68 of 102
According to Le-Chatelier's principle, exothermic reactions are favored by:
A
Increase in pressure
B
Increase in volume
C
Decrease in temperature
D
All of these
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option C: Decrease in temperature
Concept:

Exothermic reactions release heat as a product. Le Chatelier's principle states that removing a product shifts the equilibrium forward.

Formula:

$$ \text{Reactants} \rightleftharpoons \text{Products} + \text{Heat} $$

Solution:

  • Since heat is essentially a product, lowering the temperature (removing heat) creates a deficit on the right side of the equation.


  • The system shifts forward to produce more heat, thus favoring the exothermic reaction.


Why other options are incorrect:

Pressure and volume changes depend strictly on the change in gas moles (\( \Delta n \)), NOT on whether the reaction is exothermic or endothermic.

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 Equilibrium 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