Concept explainers
The following pictures represent solutions that contain one or more of the compounds H2A, NaHA, and Na2A, where H2A is a weak diprotic acid. (Na+ ions and solvent water molecules have been omitted for clarity.)
- (a) Which of the solutions are buffer solutions?
- (b) Which solution has the greatest buffer capacity?
(a)
Interpretation:
The buffer solutions should be given from the given representations.
Concept introduction:
Buffer solution:
An equal concentrations of conjugate acid-base pair in a solution is known as buffer solution and it will maintain the
Explanation of Solution
Reason for the correct option:
The given representations are,
Figure 1
From the above given representations, pictures (1) and (4) are represents the buffer solutions because they are only have a conjugate acid-base pair.
Reason for the incorrect options:
Pictures (2) and (3) don’t have a conjugate acid-base pair so they are not a buffer solutions.
The pictures (1) and (4) are represents the buffer solutions.
(b)
Interpretation:
The greatest buffer capacity having buffer solutions should be given from the given representations.
Concept introduction:
Buffer solution:
An equal concentrations of conjugate acid-base pair in a solution is known as buffer solution and it will maintain the
The buffer capacity is directly proportional to the concentrations (number) of conjugate acid-base pair in a solution.
Explanation of Solution
Reason for the correct option:
The given representations are,
Figure 1
From the above given representations, picture (4) has more number of conjugate acid-base pairs than (1) so it has greatest buffer capacity.
Reason for the incorrect options:
Pictures (2) and (3) don’t have a conjugate acid-base pair so they are not a buffer solutions and Pictures (1) has the lower number of conjugate acid-base pair than (4) so it has a smallest buffer capacity than (4).
The pictures (4) has the highest buffer capacity.
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Chapter 15 Solutions
General Chemistry: Atoms First
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