Consider the decomposition of calcium carbonate:
Calculate the pressure in atm of CO2 in an equilibrium process (a) at 25°C and (b) at 800°C. Assume that ΔH° = 177.8 kJ/mol and ΔS° = 160.5 J/K · mol for the temperature range.
(a)
Interpretation:
The equilibrium pressure (
Concept Information:
Equilibrium constant: Concentration of the products to the respective molar concentration of reactants it is called equilibrium constant. If the K value is less than one the reaction will move to the left side and the K values is higher (or) greater than one the reaction will move to the right side of reaction.
Kp: The equilibrium constant calculated from the partial pressures of a reaction equation. It is used to express the relationship between product pressures and reactant pressures. It is unites number, although it relates the pressures.
Thermodynamics is the branch of science that relates heat and energy in a system. The laws of thermodynamics explain the fundamental quantities such as temperature, energy and randomness in a system. Entropy is the measure of randomness in a system. For a spontaneous process there is always a positive change in entropy. Free energy (Gibbs free energy) is the term that is used to explain the total energy content in a thermodynamic system that can be converted into work. The free energy is represented by the letter G. All spontaneous process is associated with the decrease of free energy in the system. The equation given below helps us to calculate the change in free energy in a system.
Where,
Explanation of Solution
The calcium carbonate decomposition equilibrium expression given by,
(b)
Interpretation:
The equilibrium pressure (
Concept Information:
Equilibrium constant: Concentration of the products to the respective molar concentration of reactants it is called equilibrium constant. If the K value is less than one the reaction will move to the left side and the K values is higher (or) greater than one the reaction will move to the right side of reaction.
Kp: The equilibrium constant calculated from the partial pressures of a reaction equation. It is used to express the relationship between product pressures and reactant pressures. It is unites number, although it relates the pressures.
Thermodynamics is the branch of science that relates heat and energy in a system. The laws of thermodynamics explain the fundamental quantities such as temperature, energy and randomness in a system. Entropy is the measure of randomness in a system. For a spontaneous process there is always a positive change in entropy. Free energy (Gibbs free energy) is the term that is used to explain the total energy content in a thermodynamic system that can be converted into work. The free energy is represented by the letter G. All spontaneous process is associated with the decrease of free energy in the system. The equation given below helps us to calculate the change in free energy in a system.
Where,
Explanation of Solution
First we calculate the enthalpy and entropy values for given decomposition reaction at
Calcium carbonate, partial pressure
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Chapter 17 Solutions
CHEMISTRY 3
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