Question: Antimony (V) chloride, SbCl5, dissociates on heating to SbCl5(g)goes to SbCl3(g)+ Cl2(g). A closed 3.50 L vessel initially contains 0.0125 mol SbCl5. what is the total pressure at 248 degree's C when equilibrium is achieved? The value of Kc at 248 degree C is 2.50E-2.
How would you go about solving this problem? Would you do an ICE table? How would you find total pressure?
I think I would convert 0.0125 moles SbCl5 in 3.5 L to concn, then do an ICE table, and calculate concns of each specie. Convert M of each to moles, add moles to get total moles, then PV = nRT. I think that will do it. Check my thinking.
To solve this problem, we can use the concept of equilibrium and the given equilibrium constant (Kc) value. We will start by setting up an ICE table, which stands for Initial, Change, and Equilibrium.
1. Initial: In the 3.50 L vessel, we have 0.0125 mol of SbCl5 initially. Therefore, the initial moles of SbCl5, SbCl3, and Cl2 are as follows:
- Moles of SbCl5: 0.0125 mol
- Moles of SbCl3: 0 mol (initially)
- Moles of Cl2: 0 mol (initially)
2. Change: As the reaction progresses, SbCl5 decomposes into SbCl3 and Cl2. Let's assume that x mol of SbCl5 reacts, which means x mol of SbCl3 and x mol of Cl2 are produced.
3. Equilibrium: Using the information from the ICE table, we can write the equilibrium expression based on the balanced chemical equation:
Kc = [SbCl3] * [Cl2] / [SbCl5]
Now, let's express the equilibrium concentrations in terms of x:
[SbCl5] = (0.0125 - x) mol/L
[SbCl3] = x mol/L
[Cl2] = x mol/L
Substituting these values into the equilibrium expression, we get:
Kc = (x)(x) / (0.0125 - x)
Given that the equilibrium constant (Kc) is 2.50E-2, we can now solve this quadratic equation for x using the equation Kc = products/reactants.
Once we find the value of x, we can calculate the concentrations of all the species at equilibrium and then find the total pressure at 248 degrees Celsius when equilibrium is achieved.
To determine the total pressure, we will use the ideal gas law:
PV = nRT
Here, P is the total pressure, V is the volume of the vessel (3.50 L), n is the total moles of gas present at equilibrium (which can be calculated from the equilibrium concentrations), R is the ideal gas constant, and T is the temperature in Kelvin (248 degrees Celsius = 521 K).
Substituting these values into the ideal gas law, we can solve for the total pressure (P).