Interpretation:
The general misconception that is adding salt in water helps to cook spaghetti faster should be explained. The boiling point of salted water should be calculated and the does this temperature increase will make more difference in cooking time should be identified.
Concept Introduction:
Boiling point is the temperature at which liquid turns into a gas. Example: boiling point of water is
Where,
The Boiling point elevation
Where,
Answer to Problem 12.144QP
The boiling point increase was calculated as
Explanation of Solution
The increase in boiling point of salted solution is calculated by first determining the concentration of salt in the salted water used to cook spaghetti.
Calculate
Assuming that one table spoon of salt contains
Calculate mass of water:
The mass of water determined by assuming one table spoon of salt added to 5 quarts of water.
Calculate molality of the salted solution:
The molality of solution was calculated by dividing solute moles and mass of solvent.
Calculate the increase in boiling point:
Generally, i is the value that denotes the number of ions, those are obtained after dissociation of electrolyte.
For example the i value for
The boiling point increase was calculated by multiplying the Von’t Hoff’s factor of
The general misconception that is adding salt in water helps to cook spaghetti faster was explained. The boiling point of salted water was calculated and this temperature increase does not make more difference in cooking time.
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Chapter 12 Solutions
Chemistry
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