Concept explainers
Interpretation:
The final temperature of
Concept Introduction:
The standard enthalpy change for a reaction is the amount of enthalpy change thatoccurs at the standard conditions.
The standard enthalpy of the reaction is to be determined using the equation as given below:
Here, the
The standard enthalpy of formation is the amount of heat change when one mole of compound is formed from its integral elements that are present in their standard states.
The heat is related to the change in temperature of a material, which is as follows:
Here, q represents heat, s signifies specific heat, m shows mass, and
Answer to Problem 136AP
Solution:
a)
b)
Explanation of Solution
a)The final temperature of the product
Mass of water is
The reaction for quicklime is as follows:
The reaction for slaked lime is as follows:
The molar mass of
The number of moles is calculated by the expression, which isas follows:
Substitute
As water and
Similarly, the mole ratio of
The molar mass of
To calculate the mass of
Substitute
So, the heat produced by
Substitute
The relation between theheat and change in the temperature of a materialis given as follows:
The specific heat(s) of
Substitute
The temperature change is calculated as follows:
The change in the temperature of the material is given by the expression, which is as follows:
So, the final temperature is calculated as follows:
b) The standard enthalpy of formation of
Standard enthalpy of formation of
The reaction for slaked lime is as follows:
From appendix 2, the enthalpies of formation values of the given compounds are given as follows:
The standard enthalpy of reaction is calculated by the expression, as follows:
Now, the standard enthalpy of the given reaction is calculated as follows:
This can be rearranged and solved as follows:
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Chapter 5 Solutions
Loose-leaf Version For Chemistry
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