# Given the following equation:

SO2 + NO2 <--> SO3 + NO

At 25 Celcius, 2.00 mol of each of SO2 and NO2 are introduced into a 1.0L sealed flask. When euilibrium is reached, it is found that
[NO2] = 1.30 mol/L
[SO3] = 1.30 mol/L

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Calculate the concentration at equilibrium of SO2 and NO2.

and Calculate the K value at 25 degrees Celcius

If 1.3 moles of each reactant is used, then 2 minus that is how much remains.

concentration = amount left/volume

## To calculate the concentration at equilibrium of SO2 and NO2, we first need to find the amount of each substance that remains in the flask at equilibrium.

Given that initially we have 2.00 mol of both SO2 and NO2, and at equilibrium [NO2] = 1.30 mol/L, we can calculate the amount of NO2 that is left by subtracting the equilibrium concentration from the initial amount:

Amount of NO2 left = Initial amount of NO2 - Equilibrium concentration of NO2
= 2.00 mol - 1.30 mol/L * 1.0 L
= 0.70 mol

Similarly, since [SO3] = 1.30 mol/L at equilibrium, the amount of SO3 that has reacted can be calculated as:

Amount of SO3 reacted = Initial amount of SO2 - Equilibrium concentration of SO2
= 2.00 mol - 1.30 mol/L * 1.0 L
= 0.70 mol

Since the stoichiometric coefficient of SO2 and NO2 in the balanced equation is 1:1, the amount of SO2 left would be the same as the amount of SO3 reacted:

Amount of SO2 left = Amount of SO3 reacted = 0.70 mol

Therefore, the concentration at equilibrium for both SO2 and NO2 is:

[SO2] = Amount of SO2 left / Volume of the flask = 0.70 mol / 1.0 L = 0.70 mol/L
[NO2] = Amount of NO2 left / Volume of the flask = 0.70 mol / 1.0 L = 0.70 mol/L

Now, to calculate the equilibrium constant (K value), we can use the expression:

K = [SO3] * [NO] / ([SO2] * [NO2])

From the given information, we know that [SO3] = 1.30 mol/L and [NO2] = 1.30 mol/L. However, we don't have the concentration of NO at equilibrium. To find it, we need to use the stoichiometry of the balanced equation. Since the stoichiometric coefficient of NO2 and NO in the balanced equation is 1:1, the concentration of NO would be the same as the concentration of NO2 at equilibrium:

[NO] = [NO2] = 1.30 mol/L

Plugging these values into the equilibrium constant expression:

K = [SO3] * [NO] / ([SO2] * [NO2])
= 1.30 mol/L * 1.30 mol/L / (0.70 mol/L * 0.70 mol/L)
= 2.99

Therefore, the equilibrium constant (K value) at 25 degrees Celcius is approximately 2.99.