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Ch.15 - Chemical Equilibrium
Chapter 15, Problem 113

When 9.25 g of ClF3 was introduced into an empty 2.00-L container at 700.0 K, 19.8% of the ClF3 decomposed to give an equilibrium mixture of ClF3, ClF, and F2. ClF3 (g) ⇌ ClF (g) + F2 (g). (a) What is the value of the equilibrium constant Kc at 700.0 K? (b) What is the value of the equilibrium constant Kp at 700.0 K? (c) In a separate experiment, 39.4 g of ClF3 was introduced into an empty 2.00-L container at 700.0 K. What are the concentrations of ClF3, ClF, and F2 when the mixture reaches equilibrium?

Verified step by step guidance
1
Step 1: Calculate the initial concentration of ClF3. Use the formula: \( \text{Concentration} = \frac{\text{moles}}{\text{volume}} \). First, convert the mass of ClF3 to moles using its molar mass.
Step 2: Determine the change in concentration due to decomposition. Since 19.8% of ClF3 decomposes, calculate the moles of ClF3 that decomposed and the moles of ClF and F2 formed.
Step 3: Write the expression for the equilibrium constant \( K_c \) using the equilibrium concentrations of ClF3, ClF, and F2. \( K_c = \frac{[\text{ClF}][\text{F}_2]}{[\text{ClF}_3]} \). Substitute the equilibrium concentrations into this expression.
Step 4: Relate \( K_c \) to \( K_p \) using the equation \( K_p = K_c(RT)^{\Delta n} \), where \( \Delta n \) is the change in moles of gas, \( R \) is the ideal gas constant, and \( T \) is the temperature in Kelvin.
Step 5: For the separate experiment, calculate the initial concentration of ClF3 with the new mass. Use the same decomposition percentage to find the equilibrium concentrations of ClF3, ClF, and F2, and apply the equilibrium constant to verify the concentrations.
Related Practice
Open Question
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