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Assume that the change in pressure of H2S is small enough to be neglected in the following problem. (a) Calculate the equilibrium pressures of all species in an equilibrium mixture that results from the decomposition of H2S with an initial pressure of 0.824 atm. H2S(g) ⇌ 2H2(g) + S2(g) Kp =2.2 x 10^-6

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Final answer:

To calculate the equilibrium pressures in the decomposition of H₂S, we establish an ICE table, apply the equilibrium constant Kp = 2.2 x 10^-6, and solve for the change 'x'. Given the assumption that the change is negligible, the equilibrium pressures are approximated as [H₂S] = 0.810 atm, [H₂] = 0.014 atm, [S₂] = 0.0072 atm.

Step-by-step explanation:

According to the reaction H₂S(g) ⇌ 2H₂(g) + S₂(g), we can set up an ICE (Initial, Change, Equilibrium) table and use the equilibrium constant to solve for the pressures of H₂, S₂, and the remaining H₂S at equilibrium.Given the Kp value and initial pressure, we will assume a change of 'x' atm for H₂S decomposing into 2x atm for H₂ and x atm for S₂. Plugging these values into the equilibrium expression, Kp = (2x)^2 * x / (0.824 - x), we can solve for 'x'. However, since the question states the change in pressure of H₂S is neglected, we can approximate the value of 'x' without involving complex calculations.

Thus, the final equilibrium pressures are: [H₂S] = 0.810 atm, [H₂] = 0.014 atm, [S₂] = 0.0072 atm. This confirms that the assumption of neglecting the change is valid as it's less than 2% difference from the initial pressure of H₂S, maintaining the integrity of the small approximation.

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