Concept explainers
Interpretation:
The amount of energy released when the molten zinc metal cools, solidifies and further cools to
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 95E
The amount of energy released cooling, solidifying and further cooling zinc metal to
Explanation of Solution
Zinc solidifies at
The amount of energy released when temperature changes from
Where,
•
•
•
•
The specific heat of zinc is
Substitute the mass, final, initial temperature and specific heat of zinc in equation (1).
The amount of energy required for phase transformation is calculated by the formula shown below.
Where,
•
The heat of fusion of zinc is
Substitute the mass and heat of fusion in equation (2).
The amount of energy required to raise the temperature of zinc from
Where,
•
•
•
•
The specific heat of zinc is
Substitute the mass, final, initial temperature and specific heat of zinc in equation (3).
The total amount of energy required to cool, solidify and further cool metal at
Convert
The amount of energy released cooling, solidifying and further cooling zinc metal to
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Chapter 15 Solutions
EBK INTRODUCTORY CHEMISTRY: AN ACTIVE L
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