When Phosphorus Pentachloride, PCl₅, Is Heated at a Constant Pressure

question 12

Multiple Choice

When phosphorus pentachloride, PCl₅, is heated at a constant pressure of exactly 1 bar to a temperature of 1400 K, the amount of phosphorus pentachloride decreases by 20.7% because of dissociation to phosphorus trichloride, PCl₃, and chlorine, Cl₂. Determine the equilibrium constant at this temperature.

• A) 42.8  10^-3
• B) 87.7
• C) 0.207
• D) 0.045

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Definitions:

Potassium

A chemical element with symbol K and atomic number 19, essential for various bodily functions including neural activity and muscle contraction.

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