For the system CaO(s) + CO2(g) = CaCO3(s), I added 1.00 mol of CaO(s) to 1.00L of 0.500M CO2(g) at 200C. At equilibrium the [CO2] = 0.150M. What is the value of Kp for this reaction?
A. 0.172 B. 0.150 C. 5.82 D. 6.67 E. 2.59
Kp = pCO2
so would the answer be B?
No, and I gave you the wrong information because I didn't see an arrow sign and I though the CO2 was a product. It isn't, it's a reactant. Therefore,
Kp = 1/pCO2.
You need to find the partial pressure of the CO2 which you can do from PV = nRT.
You know V= 1L, you know R, T is 473K and n = number of mols. Since (CO2) = 0.150M and you have 1L, that is M x L = 0.150 moles. Substitute into PV = nRT and solve for pCO2. Then the reciprocal will give you Kp.
I get answer 0.172. Is that correct?
To determine the value of Kp for the given reaction, you need to establish the expression for the equilibrium constant, Kp, from the balanced chemical equation.
The balanced equation for the reaction is:
CaO(s) + CO2(g) ⇌ CaCO3(s)
In this equation, the stoichiometric coefficients are 1 for CaO(s), 1 for CO2(g), and 1 for CaCO3(s).
The expression for Kp is:
Kp = (P(CaCO3)) / (P(CO2))
In the given problem, you are provided with initial and equilibrium concentrations of CO2, so you need to convert the concentrations into partial pressures using the ideal gas law:
PV = nRT
Given:
Initial concentration of CO2, [CO2] = 0.500 M
Initial pressure, P(CO2) = [CO2] * R * T = 0.500 * R * 473 K = 236.5 R
Equilibrium concentration of CO2, [CO2] = 0.150 M
Equilibrium pressure, P(CO2) = [CO2] * R * T = 0.150 * R * 473 K = 70.59 R
Substituting these values into the expression for Kp:
Kp = (P(CaCO3)) / (P(CO2)) = (70.59 R) / (236.5 R) = 0.298
Therefore, the value of Kp for this reaction is 0.298.
None of the given options matches this value, so it seems like there might be a calculation error or a typo in the options. You may double-check your calculations or refer to the original source for the correct answer.