Asked in PMC Practice Test 30 (2021) 2021Moderate

With different number of moles of reactants and product, what happens to the volume of the system?

Correct answer: B. It changes

  • A. It remains unchanged
  • B. It changes
  • C. It decreases
  • D. It increases

Explanation

According to the ideal gas law, PV = nRT, the volume of a gas is directly proportional to the number of moles of gas present (n), assuming constant pressure (P), temperature (T), and gas constant (R). Therefore, if the number of moles of reactant and product in a chemical reaction are different, the volume of the system will generally change. Hence, option B is correct.

Last updated

About Le Chatelier's Principle

Le Chatelier's principle predicts how an equilibrium responds when concentration, pressure or temperature changes. Questions apply it to reversible reactions, identify the direction of shift and distinguish genuine equilibrium changes from the effect of a catalyst, which changes the rate of reaching equilibrium but not its position.

Practise Chemical Equilibrium

625 free Chemical Equilibrium MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.

Exams that ask Chemistry questions like this

Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.

Related questions