Equilibrium Constants and Partial Pressures

The video tutorial explains the process of calculating equilibrium partial pressures and the equilibrium constant (Kp) for the decomposition of phosphorus pentachloride (PCl5) into phosphorus trichloride (PCl3) and chlorine (Cl2) at 500 Kelvin. It begins with setting up the reaction in a flask and measuring initial pressures. An ICE table is used to determine changes in partial pressures, and Dalton's Law is applied to find equilibrium pressures. Finally, the equilibrium constant expression is derived and solved using the calculated pressures.

What is the initial pressure of PCl5 in the flask?

• 1.6 atmospheres

• 2.35 atmospheres

• 0.97 atmospheres

• 0.69 atmospheres

What is the purpose of using an ICE table in this problem?

• To measure temperature changes

• To determine the volume of the flask

• To calculate equilibrium partial pressures

• To find the molecular weight of PCl5

In the ICE table, what does the 'C' stand for?

• Coefficient

• Concentration

• Change in partial pressure

• Constant

What is the mole ratio of PCl5 to PCl3 in the reaction?

• 1:1

• 2:1

• 1:3

• 1:2

According to Dalton's Law, what is the total pressure of the gases at equilibrium?

• 2.35 atmospheres

• 0.97 atmospheres

• 0.69 atmospheres

• 1.6 atmospheres

What is the equilibrium partial pressure of Cl2?

• 0.97 atmospheres

• 2.35 atmospheres

• 0.69 atmospheres

• 1.66 atmospheres

What is the equilibrium partial pressure of PCl5 after the reaction?

• 0.69 atmospheres

• 2.35 atmospheres

• 1.66 atmospheres

• 0.97 atmospheres

What is the expression for the equilibrium constant Kp for this reaction?

• (PCl5) / (PCl3 + Cl2)

• (PCl3 + Cl2) / PCl5

• (PCl3 * Cl2) / PCl5

• (PCl5) / (PCl3 * Cl2)

What is the calculated value of Kp at 500 Kelvin?

• 0.49

• 2.35

• 0.97

• 1.66

Which of the following is a product in the reaction?

• PCl5

• H2O

• O2

• PCl3