Concept explainers
Interpretation:
The change in temperature for a reaction is to be determined.
Concept introduction:
Heat absorbed or released in a reaction is associated with the change in temperature in the reaction, which is determined as follows:
Where,
Specific heat is the heat required to increase the temperature of
The concentration (molarity) of a solution is determined by the following equation:
Where,
Answer to Problem 138AP
Solution: The change in temperature is
Explanation of Solution
Given information: A
The concentration (molarity) of a solution is determined by the following equation:
It can be rewritten as:
The equation for ionization of
From the reaction above, it is clear that the number of moles of HBr and H are equal.
So, the number of moles of
Substitute
The equation for ionization of
From the reaction, it is clear that the number of moles of
So, the number of moles of
Substitute
So,
Now, heat produced by the reaction is calculated as:
Substitute
As it is known that
So, heat is given by:
Mass of
Here,
Substitute
Now, substitute
Now, the change in temperature is determined by the following equation:
Here,
Equation
Substitute
The change in temperature for the given reaction is
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Chapter 5 Solutions
Chemistry
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