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At 55 degrees celcius, the K for the reaction: 2NO2 (g) <=> N2O4(g) is 1.15

Calculate the concentration of N2)4(g) present in equilibrium with 0.50 mole of NO2.

Please help. Thanks!

To calculate the concentration of N2O4 present in equilibrium with 0.50 moles of NO2, we can use the equilibrium constant (K) and the stoichiometry of the reaction.

First, let's define the reaction:

2NO2(g) <=> N2O4(g)

According to the given information, at 55 degrees Celsius, the value of K for this reaction is 1.15. The equilibrium constant expression is:

K = [N2O4] / [NO2]^2

where [N2O4] represents the concentration of N2O4 and [NO2] represents the concentration of NO2.

Since the initial concentration of NO2 is given as 0.50 moles, we need to determine the equilibrium concentrations.

Let's assume that the change in concentration of N2O4 (x) is the same as the change in concentration of NO2. Therefore, the equilibrium concentrations can be written as follows:

[N2O4] = x
[NO2] = 0.50 - x

Now, substitute these equilibrium concentrations into the equilibrium constant expression:

1.15 = [N2O4] / [NO2]^2
1.15 = x / (0.50 - x)^2

Solving this equation will give us the value of x, which represents the equilibrium concentration of N2O4. Once we have x, we can calculate the concentration of N2O4 by substituting it back into the equilibrium concentrations equation.

To summarize:
1. Set up the equilibrium constant expression and substitute the given values:
K = 1.15
[NO2] = 0.50
[N2O4] = x

2. Rearrange the expression and solve for x:
1.15 = x / (0.50 - x)^2

3. Once you find the value of x, substitute it back into the equilibrium concentrations equation to find [N2O4].

Note: This calculation requires algebraic manipulation and solving a quadratic equation. Thus, you can use a graphing calculator, an online equation solver, or solve it manually using algebraic techniques.