The Decomposition Of Calcium Carbonate, C A C O 3 ( S ) → C A O ( S ) + C O 2 ( G CaCO_3(s) \rightarrow CaO(s) + CO_2(g C A C O 3 ​ ( S ) → C A O ( S ) + C O 2 ​ ( G ], Has The Following Values For Free Energy And Enthalpy At 25.0 ∘ C 25.0^{\circ} C 25. 0 ∘ C :$[ \begin{array}{l} \Delta G = 130.5 , \text{kJ/mol} \ \Delta H = 178.3

The Decomposition of Calcium Carbonate: Understanding the Thermodynamic Properties

The decomposition of calcium carbonate, $CaCO_3(s) \rightarrow CaO(s) + CO_2(g)$, is a thermodynamically favored reaction at high temperatures. However, at room temperature, the reaction is not spontaneous, and the reaction rate is slow. In this article, we will discuss the thermodynamic properties of the decomposition reaction, including the free energy and enthalpy values at $25.0^{\circ} C$. Understanding these properties is crucial in predicting the spontaneity and feasibility of the reaction.

The decomposition reaction of calcium carbonate is an endothermic reaction, meaning that it absorbs heat from the surroundings. The enthalpy change ($\Delta H$) for the reaction is $178.3 \, \text{kJ/mol}$. This value indicates that the reaction requires a significant amount of energy to proceed.

The free energy change ($\Delta G$) for the reaction is $130.5 \, \text{kJ/mol}$. The free energy change is a measure of the spontaneity of the reaction. A negative free energy change indicates that the reaction is spontaneous, while a positive free energy change indicates that the reaction is non-spontaneous.

Understanding the Free Energy Change

The free energy change ($\Delta G$) is related to the enthalpy change ($\Delta H$) and the entropy change ($\Delta S$) by the following equation:

$$\Delta G = \Delta H - T\Delta S$$

where $T$ is the temperature in Kelvin. At $25.0^{\circ} C$, the temperature is $298 \, \text{K}$.

To calculate the entropy change ($\Delta S$), we can use the following equation:

$$\Delta S = \frac{\Delta H - \Delta G}{T}$$

Substituting the values of $\Delta H$ and $\Delta G$, we get:

$$\Delta S = \frac{178.3 \, \text{kJ/mol} - 130.5 \, \text{kJ/mol}}{298 \, \text{K}} = 0.234 \, \text{kJ/mol} \cdot \text{K}$$

The entropy change ($\Delta S$) is a measure of the disorder or randomness of the system. A positive entropy change indicates that the system becomes more disordered or random, while a negative entropy change indicates that the system becomes more ordered or less random.

Interpreting the Thermodynamic Properties

The thermodynamic properties of the decomposition reaction of calcium carbonate can be interpreted as follows:

• The positive free energy change ($\Delta G$) indicates that the reaction is non-spontaneous at room temperature.
• The positive enthalpy change ($\Delta H$) indicates that the reaction is endothermic and requires a significant amount of energy to proceed.
• The positive entropy change ($\Delta S$) indicates that the system becomes more disordered or random during the reaction.

In conclusion, the decomposition reaction of calcium carbonate is a thermodynamically favored reaction at high temperatures. However, at room temperature, the reaction is not spontaneous, and the reaction rate is slow. Understanding the thermodynamic properties of the reaction, including the free energy and enthalpy values, is crucial in predicting the spontaneity and feasibility of the reaction.

• [1] Atkins, P. W., & De Paula, J. (2010). Physical chemistry (9th ed.). Oxford University Press.
• [2] Chang, R. (2010). Chemistry: The central science (11th ed.). McGraw-Hill.

For further reading on the thermodynamic properties of the decomposition reaction of calcium carbonate, we recommend the following articles:

• "The Decomposition of Calcium Carbonate: A Thermodynamic Study" by J. Smith and R. Johnson
• "The Kinetics of the Decomposition of Calcium Carbonate" by M. Brown and J. Davis

The following table summarizes the thermodynamic properties of the decomposition reaction of calcium carbonate:

Note: The values are given in units of kJ/mol.
Frequently Asked Questions (FAQs) about the Decomposition of Calcium Carbonate

A: The decomposition reaction of calcium carbonate is a chemical reaction in which calcium carbonate ($CaCO_3$) breaks down into calcium oxide ($CaO$) and carbon dioxide ($CO_2$). The reaction is represented by the following equation:

$CaCO_3(s) \rightarrow CaO(s) + CO_2(g)$

A: The thermodynamic properties of the decomposition reaction of calcium carbonate include the free energy change ($\Delta G$), enthalpy change ($\Delta H$), and entropy change ($\Delta S$). The values of these properties at $25.0^{\circ} C$ are:

• $\Delta G = 130.5 \, \text{kJ/mol}$
• $\Delta H = 178.3 \, \text{kJ/mol}$
• $\Delta S = 0.234 \, \text{kJ/mol} \cdot \text{K}$

A: No, the decomposition reaction of calcium carbonate is not spontaneous at room temperature. The positive free energy change ($\Delta G$) indicates that the reaction is non-spontaneous.

A: The decomposition reaction of calcium carbonate is an endothermic reaction, meaning that it absorbs heat from the surroundings. As the temperature increases, the reaction becomes more spontaneous, and the reaction rate increases.

A: The entropy change ($\Delta S$) is a measure of the disorder or randomness of the system. In the decomposition reaction of calcium carbonate, the entropy change is positive, indicating that the system becomes more disordered or random during the reaction.

A: Yes, the decomposition reaction of calcium carbonate can be catalyzed by certain substances, such as acids or bases. The catalyst can lower the activation energy of the reaction, making it more spontaneous and increasing the reaction rate.

A: The decomposition reaction of calcium carbonate has several applications, including:

• Production of calcium oxide (quicklime) for use in construction and manufacturing
• Production of carbon dioxide for use in industrial processes, such as carbonation of beverages
• Study of thermodynamic properties and kinetics of chemical reactions

A: When handling calcium carbonate, it is essential to wear protective gear, including gloves, goggles, and a mask. Calcium carbonate can be hazardous if inhaled or ingested, and it can cause skin and eye irritation.

A: Yes, the decomposition reaction of calcium carbonate can be reversed by reacting calcium oxide with carbon dioxide to form calcium carbonate. This reaction is represented by the following equation:

$CaO(s) + CO_2(g) \rightarrow CaCO_3(s)$

Note: The values are given in units of kJ/mol.