(a)
Interpretation:
The common-ion effect needs to be explained.
Concept introduction:
Any atom or a molecule with a net charge is known as an ion. The net charge of an electron is opposite and equal to a proton. The net charge of an ion is never zero. This is due to the number of electrons being unequal to the number of protons.
Common ion effect is an effect in which several species of reversibly associated chemical solutions increase the concentration of any of its components by an equilibrium process.
(b)
Interpretation:
The use of a buffer solution to maintain a constant pH value needs to be explained.
Concept introduction:
A buffer solution is a mixture of a weak base and a conjugate acid or vice versa. The pH of a buffer solution changes very little when on adding a small amount of strong acid or a strong base to it.
The pH value indicates the acidic or basic nature of the given solution.
(c)
Interpretation:
The determination of pKa of a weak acid from a titration curve needs to be explained.
Concept introduction:
Titration is the process of identifying the concentrations of an unknown solution with the given concentrations of another solution.
The titration curve is used to plot the values determined after the process of titration.
It is an easy method of recording observations after the titration process.
pKa value determines the value of acidic strength. It is given by the negative log of an acid. This is the ka value.
Lower the pKa value stronger will be the acid.
(d)
Interpretation:
The measurement of pH with an acid-base indicator needs to be explained.
Concept introduction:
An ion or a molecule capable of donating a proton is known as an acid.
Substances that release hydrogen ions in an aqueous solution are called bases.
pH indicators are used to indicate the acidic or basic nature of a solution by changing its color.
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General Chemistry: Principles and Modern Applications (11th Edition)
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