(a)
Interpretation: Standard enthalpy of the reaction and change in standard entropy of the given reaction are to be determined and the temperature at which the change in standard Gibb’s energy is zero, is to be calculated.
Concept introduction: The standard enthalpy of the reaction is calculated by the formula,
The change in standard Gipp’s free energy of the reaction is calculated as,
To determine: Standard enthalpy of the reaction and change in standard entropy of the given reaction.
(a)
Answer to Problem 87CWP
Standard enthalpy of the reaction and change in standard entropy of the given reaction is
Explanation of Solution
Hydrogen gas is produced by reacting graphite with water.
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of formation of
The standard enthalpy of the reaction is calculated by the formula,
Therefore, the above equation becomes,
Substitute the value of
Therefore, the standard enthalpy of the reaction is
The standard entropy of
The standard entropy of
The standard entropy of
The standard entropy of
The standard entropy change of the reaction is calculated by the formula,
Therefore, the above equation becomes,
Substitute the value of
Therefore, the standard entropy change of the reaction is
(b)
Interpretation: Standard enthalpy of the reaction and change in standard entropy of the given reaction are to be determined and the temperature at which the change in standard Gibb’s energy is zero, is to be calculated.
Concept introduction: The standard enthalpy of the reaction is calculated by the formula,
The change in standard Gipp’s free energy of the reaction is calculated as,
To determine: The temperature at which the change in standard Gipp’s energy of the given reaction is zero.
(b)
Answer to Problem 87CWP
The temperature at which the change in standard Gipp’s energy of the given reaction is zero is
Explanation of Solution
Given
The change in standard Gipp’s energy of the given reaction is zero.
Standard enthalpy of the reaction and change in standard entropy of the given reaction is
The change in standard Gipp’s free energy of the reaction is calculated as,
Substitute the value of
Therefore, the temperature at which the change in standard Gipp’s energy of the given reaction is zero is
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Chapter 19 Solutions
EBK CHEMISTRY: AN ATOMS FIRST APPROACH
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- The combustion of acetylene, C2H2, is a spontaneous reaction given by the equation 2C2H2(g)+5O2(g)4CO2(g)+2H2O(l) As expected for a combustion, the reaction is exothermic. What is the sign of H? What do you expect for the sign of S? Explain the spontaneity of the reaction in terms of the enthalpy and entropy changes.arrow_forwardElemental boron, in the form of thin fibers, can be made by reducing a boron halide with H2. BCl3(g) + 32 H2(g) B(s) + 3 HCl(g) Calculate rH, rS, and rG at 25 C for this reaction. Is the reaction predicted to be product-favored at equilibrium at 25 C? If so, is it enthalpy- or entropy-driven? [S for B(s) is 5.86 J/K mol.]arrow_forwardFor each process, predict whether entropy increases or decreases, and explain how you arrived at your prediction. 2 CO2(g) → 2 CO(g) + O2(g) NaCl(s) → NaCl(aq) MgCO3(s) → MgO(s) + CO2(g)arrow_forward
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