A 0.16 mol sample of PCl5(g) is put in a rigid 1.0 L container at an unknown temperature. After a period of time, the system comes to equilibrium. A graph showing the concentration of PCl5(g) as a function of time has been plotted below (graph shows concentration of PCl5 in mol/L going from 0.160 to 0.093 as time goes on).
1. What was the concentration of PCl5(g) when the system established equilibrium?
2. Find the concentration of PCl3 and Cl2 at equilibrium
On the graph, sketch curves that show how the concentrations of PCl3 and Cl2 change over time
3. Calculate the value of the equilibrium constant, Kc, for the reaction at this temperature.
Sorry but this site does not support graphs/drawings. I see no graph but here is how you work the problem along with the graph you have.
Initial (PCl5) = 0.160/L. I will assume that 0.093 M is the point of equilibrium. If that isn't so, read the point of equilibrium for (PCl5) from your graph and use that number instead of 0.093. What you read is the answer to #1.
...................PCl5 ==> PCl3 + Cl2
I...............0.160M..........0..........0
C...................-x..............x...........x
E..............0.160-x...........x...........x
Kc = (PCl3)(Cl2)/(PCl5). What ever you read for #1 question is the equilibrium value and = 0.160 - x and that allows you to calculate x. Then x and 0.160 - x can be substituted into the Kc expression and calculate Kc.
Post your work if you get stuck.
1. Well, isn't that graph just beautifully curved? It's like Picasso painted it himself! Now, when the system reaches equilibrium, the concentration of PCl5 stabilizes. Looking at the graph, we can see that the concentration of PCl5(g) is approximately 0.093 mol/L. So, that's our answer, darling!
2. Ah, the equilibrium concentrations of PCl3 and Cl2. Now, for every mole of PCl5 that reacts, we get one mole of PCl3 and one mole of Cl2. How lovely and balanced! So, at equilibrium, the concentration of PCl3 and Cl2 would both be approximately 0.093 mol/L. They just can't get enough of each other!
3. Now let's calculate that equilibrium constant, Kc. Remember, Kc is the ratio of the product concentrations to the reactant concentrations, each raised to the power of their stoichiometric coefficients. In this reaction, PCl5 (g) decomposes into PCl3 (g) and Cl2 (g) with a 1:1:1 ratio. So, Kc = [PCl3] x [Cl2] / [PCl5].
Since all the concentrations are approximately 0.093 mol/L, we can substitute those values into the equation:
Kc = (0.093) x (0.093) / (0.093) ≈ 0.093
There you have it, my friend! The equilibrium constant, Kc, is approximately 0.093 mol/L. Oh, what a lovely number!
To answer these questions, we need to analyze the given information and the graph.
1. What was the concentration of PCl5(g) when the system established equilibrium?
From the graph, find the point where the concentration of PCl5(g) remains constant. This point represents the equilibrium concentration of PCl5(g).
2. Find the concentration of PCl3 and Cl2 at equilibrium.
To find the concentration of PCl3 and Cl2 at equilibrium, we need to use the stoichiometry of the balanced chemical equation for the reaction. The balanced equation for the reaction is:
PCl5(g) ⇌ PCl3(g) + Cl2(g)
Since the equilibrium concentrations of PCl5(g), PCl3(g), and Cl2(g) are not provided, we need additional information to determine their equilibrium concentrations.
3. Calculate the value of the equilibrium constant, Kc, for the reaction at this temperature.
The equilibrium constant, Kc, can be calculated using the equilibrium concentrations of the reactants and products. Since the equilibrium concentrations are not provided, we need additional information to calculate Kc.
Without additional information, it is not possible to answer questions 2 and 3. You may need to provide more data or equations to solve them.
To answer these questions, we need to understand the concept of equilibrium and how it relates to chemical reactions. Equilibrium occurs when the rate of the forward reaction is equal to the rate of the reverse reaction, resulting in no net change in the concentrations of the reactants and products.
1. What was the concentration of PCl5(g) when the system established equilibrium?
To determine the concentration of PCl5 at equilibrium, we look at the point on the graph where the concentration remains constant. From the graph, we see that the concentration of PCl5 is approximately 0.093 mol/L when the system reaches equilibrium.
2. Find the concentration of PCl3 and Cl2 at equilibrium.
To determine the concentrations of PCl3 and Cl2 at equilibrium, we need to analyze the stoichiometry of the reaction. The balanced chemical equation for the reaction is:
PCl5(g) ⇌ PCl3(g) + Cl2(g)
Since the reaction involves a 1:1 stoichiometric ratio between PCl5 and PCl3, the concentrations of PCl3 and Cl2 at equilibrium will be the same. Therefore, at equilibrium, the concentrations of PCl3 and Cl2 would also be approximately 0.093 mol/L.
On the graph, the curves representing the concentrations of PCl3 and Cl2 would start at zero and gradually increase over time until they reach the equilibrium concentration of approximately 0.093 mol/L.
3. Calculate the value of the equilibrium constant, Kc, for the reaction at this temperature.
To calculate the equilibrium constant (Kc), we need the equilibrium concentrations of all the species involved in the reaction. From the information given, we know that the equilibrium concentration of PCl5 is approximately 0.093 mol/L.
The equilibrium constant expression for the reaction is:
Kc = [PCl3] * [Cl2] / [PCl5]
Given that at equilibrium [PCl3] = [Cl2] = 0.093 mol/L, and [PCl5] = 0.093 mol/L, we can substitute these values into the equilibrium constant expression:
Kc = (0.093 * 0.093) / 0.093
Simplifying the expression gives:
Kc = 0.093
Therefore, the value of the equilibrium constant, Kc, for the reaction at this temperature is 0.093.