A) The number of moles of COâ‚‚(g) present in the vessel at equilibrium is; 1.04 moles
B)  The expression for Kp, the equilibrium constant for the reaction, and its value at 898°C is; Kp = (P[CO₂] * P[CaO])/(P[CaCO₃]) and Kp = 0.0104 mol/L
We are given the reaction equation as;
CaCO₃ (s) ⇄ CaO (s) + CO₂(g)
We are given;
Number of moles of CaCO₃ used = 2 mols
Volume of vessel; V = 100 L
Temperature; T = 898°C = 1171 K
Pressure of COâ‚‚ in the vessel; P = 1 atm
A) Formula for number of moles of COâ‚‚ in the vessel at equilibrium is;
n = PV/RT
where;
P is Pressure
V is Volume
R is gas constant = 0.08206 L·atm/mol·k
n = (1 * 100)/(0.08206 * 1171)
n = 1.04 moles of COâ‚‚
B) Formula to find the equilibrium constant kp is;
Kp = (P[CO₂] * P[CaO])/(P[CaCO₃])
Where;
P[COâ‚‚] is the partial pressure of COâ‚‚
P[CaO] is the partial pressure of CaO
P[CaCO₃] is the partial pressure of CaCO₃
Since concentration of solids is taken as 1, then it means that;
Kp = P[COâ‚‚]
Kp = 1.04/100
Kp = 0.0104 mol/L
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