Question

consider the equilibrium system described by the chemical reaction below. at equilibrium, a 2.0 l reaction vessel contained a mixture of 1.2 mol fe, 1.0×10⁻³ mol o₂, and 2.0 mol of fe₂o₃ at 2000.0 °c. what are the values of kc and kp for this reaction? 4fe(s) + 3o₂(g) ⇌ 2fe₂o₃(s) based on the given data, set up the expression for kc. each reaction participant must be represented by one tile. do not combine terms. once the expression is constructed, solve for kc. complete parts 1 - 2 before submitting your answer. kc =

Explanation:

Step1: Write the equilibrium - constant expression for $K_c$

For the reaction $4Fe(s)+3O_2(g)
ightleftharpoons2Fe_2O_3(s)$, solids are not included in the equilibrium - constant expression. So, $K_c=\frac{1}{[O_2]^3}$.

Step2: Calculate the concentration of $O_2$

The number of moles of $O_2$ is $n = 1.0\times10^{-3}\ mol$ and the volume of the vessel $V = 2.0\ L$. The concentration of $O_2$, $[O_2]=\frac{n}{V}=\frac{1.0\times10^{-3}\ mol}{2.0\ L}=5.0\times10^{-4}\ mol/L$.

Step3: Calculate $K_c$

Substitute $[O_2]=5.0\times10^{-4}\ mol/L$ into the $K_c$ expression. $K_c=\frac{1}{(5.0\times10^{-4})^3}=\frac{1}{1.25\times10^{-10}} = 8.0\times10^{9}$.

Answer:

$8.0\times10^{9}$