Question detail
In the reaction 2A(g) + B(g) ⇌ 3C(g), if P(A) = 0.4 atm, P(B) = 0.6 atm, and P(C) = 0.9 atm, calculate Kp. What are the units of Kp (A-level cue f4864fd9 focus)
Try the question, check the answer, then read the explanation to understand the curriculum point.
At a glance
MCQ
Type
practice
Style
Topic
Equilibrium constant Kp for homogeneous systems (A-level only)
Question
- A. atm^-1
- B. atm^3 (A-level cue f4864fd9 distractor 1)
- C. atm^-2 (A-level cue f4864fd9 distractor 2)
- D. none (A-level cue f4864fd9 distractor 3)
Answer
atm^-1
Explanation
The correct option is atm^-1. atm^-1 is correct because it supports the objective: Calculate Kp and determine appropriate units.. The reasoning stays within Kp and partial pressure (A-level only) and avoids drifting into a similar A-Level Chemistry idea. This version is uniquely anchored to Kp and partial pressure (A-level only). Retrieval anchor: A-level cue f4864fd9.
Common mistake
Misidentifying the Units of Kp
Students often write the equilibrium constant Kp as a dimensionless quantity, ignoring that it is expressed in terms of pressure units such as atm or bar.
Kp must be expressed with the same pressure units as the partial pressures used in the equilibrium expression, e.g. atm, bar, or kPa. When all partial pressures are in atm, Kp is given in atm⁰⁰ (dimensionless), but the convention is to state the units explicitly as atm or bar to avoid confusion. Keep the correction anchored to Kp and partial pressure (A-level only) and the objective: Calculate Kp and determine appropriate units.
Related flashcards
Flashcard 1 of 5
Related practice questions
Question 1 of 5
Choose an answer, get feedback, then move sideways through the set.