3.1.10
Equilibrium
Constant Kp
Section 3.1.10 covers the equilibrium constant Kp for homogeneous systems: Kp is deduced from the equation for a reversible reaction in the gas phase and calculated from partial pressures at constant temperature, partial pressures come from mole fractions and the total pressure, and the section includes constructing Kp expressions, Kp calculations, the qualitative effect of temperature and pressure on the position of equilibrium and of temperature on the value of Kp, and the role of a catalyst, which changes the rate of attainment of equilibrium but not the constant.
Revision Notes
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Partial Pressures and Kp Expressions
Partial pressures and Kp: mole fraction, partial pressure from mole fraction and total pressure, and writing Kp expressions for homogeneous gas equilibria.
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Calculating Kp
Calculating Kp: equilibrium moles, mole fractions and partial pressures, the value and units of Kp in kPa, and finding a pressure from Kp.
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What Changes an Equilibrium Constant?
Equilibrium constants and conditions: the effect of temperature on Kp, and why concentration, pressure and catalysts do not change the constant.
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Equilibrium Constant Kp Map
AQA A-level Chemistry · 3.1.10 Equilibrium constant Kp for homogeneous systems
The whole section on one A4 page: mole fractions and partial pressures, writing Kp, calculating Kp, why only temperature changes Kp, and working back from Kp.
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3.1.10
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