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Calculate the equilibrium partial pressure of PCl3 in 3.00L vessel that was charged with 0.123atm of PCl5 (Keq=0.0121)

User Bzu
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Answer:

Step-by-step explanation:

To calculate the equilibrium partial pressures of the reactants and products in a chemical reaction, we need to use the given equilibrium constant (Keq) and the initial partial pressure of one of the substances. The reaction you provided is:

PCl₅ (g) ⇌ PCl₃ (g) + Cl₂ (g)

The equilibrium constant expression for this reaction is:

Keq = [PCl₃] * [Cl₂] / [PCl₅]

Given that Keq = 0.0121 and the initial partial pressure of PCl₅ is 0.123 atm, we need to find the equilibrium partial pressures of PCl₃ and Cl₂.

Let's assume that at equilibrium, the partial pressure of PCl₃ is x atm and the partial pressure of Cl₂ is also x atm.

We can set up an expression for Keq using these values:

0.0121 = (x) * (x) / (0.123)

Now we can solve for x:

0.0121 = x² / 0.123

x² = 0.0121 * 0.123

x² = 0.0014883

x = √(0.0014883)

x ≈ 0.03856 atm

So, the equilibrium partial pressures of PCl₃ and Cl₂ are both approximately 0.03856 atm.

Now, we need to calculate the equilibrium partial pressure of PCl₅, which will be the initial partial pressure minus the change in PCl₅:

Equilibrium PCl₅ = Initial PCl₅ - Change in PCl₅

Equilibrium PCl₅ = 0.123 atm - x

Equilibrium PCl₅ = 0.123 atm - 0.03856 atm

Equilibrium PCl₅ ≈ 0.08444 atm

Therefore, the equilibrium partial pressures in the 3.00 L vessel are approximately:

PCl₃: 0.03856 atm

Cl₂: 0.03856 atm

PCl₅: 0.08444 atm

User Christopher King
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