For the following reactions at constant pressure, predict if ΔH > ΔE, ΔH < ΔE, or ΔH = ΔE.
a. 2HF(g) → H2(g) + F2(g)
b. N2(g) + 3H2(g) → 2NH3(g)
c. 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g)
(a)
Interpretation:
For the given set of reactions it should be predicted that which is greater either
Concept Introduction:
Enthalpy change: It is defined as the amount of heat released or absorbed by the chemical reaction at constant pressure conditions.
Considering the following equation we can identify whether
Enthalpy change of combustion: It is the heat energy change involved when one mole of substance gets burned in pressure of oxygen under standard conditions.
Standard enthalpy of formation: It is the heat required when one mole of substance formed from its pure elements in standard state.
Hess law: It states that the total enthalpy of the reaction is equal to the sum of the enthalpy change for individual steps involved in the reaction.
To predict: Whether
Answer to Problem 54E
For the given reaction
Explanation of Solution
Analysing the given reaction shows that there are two gaseous reactants that gives rise to 2 gaseous products therefore,
For the given reaction
(b)
Interpretation:
For the given set of reactions it should be predicted that which is greater either
Concept Introduction:
Enthalpy change: It is defined as the amount of heat released or absorbed by the chemical reaction at constant pressure conditions.
Considering the following equation we can identify whether
Enthalpy change of combustion: It is the heat energy change involved when one mole of substance gets burned in pressure of oxygen under standard conditions.
Standard enthalpy of formation: It is the heat required when one mole of substance formed from its pure elements in standard state.
Hess law: It states that the total enthalpy of the reaction is equal to the sum of the enthalpy change for individual steps involved in the reaction.
To predict: Whether
Answer to Problem 54E
For the given reaction
Explanation of Solution
Analysing the given reaction shows that there are 4 gaseous reactants that gives rise to 2 gaseous products therefore,
For the given reaction
(c)
Interpretation:
For the given set of reactions it should be predicted that which is greater either
Concept Introduction:
Enthalpy change: It is defined as the amount of heat released or absorbed by the chemical reaction at constant pressure conditions.
Considering the following equation we can identify whether
Enthalpy change of combustion: It is the heat energy change involved when one mole of substance gets burned in pressure of oxygen under standard conditions.
Standard enthalpy of formation: It is the heat required when one mole of substance formed from its pure elements in standard state.
Hess law: It states that the total enthalpy of the reaction is equal to the sum of the enthalpy change for individual steps involved in the reaction.
To predict: Whether
Answer to Problem 54E
For the given reaction
Explanation of Solution
Analysing the given reaction shows that there are 9 gaseous reactants that gives rise to 10 gaseous products therefore,
For the given reaction
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