Consider the reaction.

At equilibrium, the concentrations of the different species are as follows:
[tex]\[
\begin{array}{l}
\left[ \text{NH}_3 \right] = 0.105 \, \text{M} \\
\left[ \text{N}_2 \right] = 1.1 \, \text{M} \\
\left[ \text{H}_2 \right] = 1.50 \, \text{M}
\end{array}
\][/tex]

What is the equilibrium constant for the reaction at this temperature?

A. 0.0030
B. 0.030
C. 34
D. 340



Answer :

Sure, let's solve this step-by-step.

The balanced chemical equation for the reaction is:
[tex]\[ \text{N}_2 + 3\text{H}_2 \leftrightarrow 2\text{NH}_3 \][/tex]

The equilibrium constant expression for this reaction [tex]\( K_{eq} \)[/tex] is defined as:
[tex]\[ K_{eq} = \frac{[\text{NH}_3]^2}{[\text{N}_2] \cdot [\text{H}_2]^3} \][/tex]

We are given the following equilibrium concentrations:
[tex]\[ [\text{NH}_3] = 0.105 \, M \][/tex]
[tex]\[ [\text{N}_2] = 1.1 \, M \][/tex]
[tex]\[ [\text{H}_2] = 1.50 \, M \][/tex]

Now, let's substitute these concentrations into the equilibrium constant expression:
[tex]\[ K_{eq} = \frac{(0.105)^2}{(1.1) \cdot (1.50)^3} \][/tex]

First, calculate the numerator:
[tex]\[ (0.105)^2 = 0.011025 \][/tex]

Next, calculate the denominator:
[tex]\[ (1.50)^3 = 1.50 \times 1.50 \times 1.50 = 3.375 \][/tex]
[tex]\[ 1.1 \times 3.375 = 3.7125 \][/tex]

Now, divide the numerator by the denominator:
[tex]\[ K_{eq} = \frac{0.011025}{3.7125} \approx 0.002969696969696969 \][/tex]

Looking at the provided choices, the closest value to our calculation is [tex]\( 0.0030 \)[/tex].

Therefore, the equilibrium constant [tex]\( K_{eq} \)[/tex] for the reaction at this temperature is:
[tex]\[ \boxed{0.0030} \][/tex]