Concept explainers
Interpretation:
The amount of energy gained by the sample when the temperature is changed from
Concept introduction:
The amount of energy required to change the state of a substance is known as enthalpy. It is the difference in the energy of the final and initial state of a substance. The negative and positive sign of enthalpy indicates the energy released and energy absorbed, respectively, during the phase change.
Answer to Problem 93E
The amount of energy gained by the sample when the temperature is changed from
Explanation of Solution
Three stages are involved when the temperature of ice sample is raised from
The amount of energy required to raise the temperature of ice from
Where,
•
•
•
•
The specific heat of ice is
Substitute the mass, final, initial temperature and specific heat of ice in equation (1).
The amount of energy required to melt a solid is calculated by the formula shown below.
Where,
•
The heat of fusion of water is
Substitute the mass and heat of fusion in equation (2).
The amount of energy required to raise the temperature of water from
Where,
•
•
•
•
The specific heat of water is
Substitute the mass, final, initial temperature and specific heat of water in equation (3).
The total amount of energy sample gained when temperature is changed from
Convert
The amount of energy sample gained when temperature is changed from
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Chapter 15 Solutions
Introductory Chemistry: An Active Learning Approach
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