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### Derive an expression for the degree of dissociation, α, in terms of Kp

For the homogeneous gaseous reaction 2 AB2 (g) ⇌ 2 AB (g) + B2 (g) Derive an expression for the degree of dissociation, α, in terms of Kp and total pressure P assuming that α

### The degree of dissociation of PCl5 at a certain temperature and under atmospheric pressure is 0.2. Calculate the pressure at which it will be half dissociated at the same temperature.

PCl5 dissociates as: PCl5 ⇌ PCl3 Cl2 If α is the degree of dissociation at certain temperature under atmospheric pressure, then Initial concentration: PCl5 = 1 PCl3 = 0 Cl2 = 0 At Equilibrium: PCl5 = 1 - α PCl3 = α Cl2 = α Total number of moles at equilibrium = 1 – α + ...

### At 700 K, the equilibrium constant Kp, for the reaction 2 SO3 (g) ⇌ 2 SO2 (g) + O2 Is 1.8 X 10-3 kPa. What is the numerical value in moles per liter of Kc for the reaction at the same temperature?

Relation between Kp and Kc is given as: Kp = Kc (RT) ∆n Kc = Kp / (RT) ∆n T = 700 K R = 8.314 J mol -1 K-1 ∆n = (2 + 1) – 2 = 1 Kp = 1.8 X 10-3 kPa ...

### What are the units of Equilibrium constant?

The Equilibrium constant expression involves the concentrations or partial pressures of the reactants and products. The units of Equilibrium constant K will depend on the number of moles of reactants and products. There are following two cases: Case1. When the total number of moles of products is ...

### What will be the effect of addition of inert gas on the equilibrium constant?

Effect of addition of inert gas like helium, neon etc has the following effects on the equilibrium constant: There are two cases on which equilibrium depends. These are: (1) Addition of an inert gas at constant volume: When an inert gas is added to the system in equilibrium ...

### At 540 K, 0.10 mole of PCl5 is heated in an 8.0 L flask. The pressure of the equilibrium mixture is found to be 1.0 atm. Calculate Kp and c for the reaction.

The reaction will be given as: PCl5 ⇌ PCl3 Cl2 Initial moles: PCl5 = 0.10 PCl3 = 0 Cl2 = 0 Equivalent moles: PCl5 = 0.10 - α PCl3 = α Cl2 = α Total number of moles = 0.10 – α + α + α = 0.10 + α Now, we know that pV = ...

### Explain the effect of change of pressure on Equilibrium

The change of pressure can be observed on the reactions which involves gaseous substances. According to Le-Chateliers’s principle, increase of pressure on a system at equilibrium will shift the equilibrium in the direction in which pressure is reduce. By increase in pressure, the volume occupied by ...

### Explain Le-Chateliers’s principle with example

The two French chemists, Le-Chateliers and Braun in 1884 made a certain generalizations to explain the effect of changes of system in equilibrium due to concentration, temperature or pressure. The generalization is known as Le-Chateliers’s principle. When a system is subjected to a change in ...

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