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I do not understand what Choice C is even saying, and the answer explanation is still confusing. Would someone please explain choice C for me? Thank you!!
I understand why the answer is NOT A, B, or D. But I just do not get what C is even saying, thank you!
41. Even though the NaOH concentration in the third trial is 100 times greater than the NaOH concentration in the first trial, the two graphs follow a similar slope' This is BEST explained by which of the following statements?
Note: The first trial is 25 mL 0.01 M HCI titrated by 0.01 M NaOH
The third trial is 25 mL 1.00 M HCI titrated by 1.00 M NaOH
A. The solution is a buffered solution, so the pH change is minimal.
B. The NaOH is a weak base and does not fully react with the HCl.
C. The pH is a log scale, so as the pH increases up to 7.0, the amount of base necessary to increase the pH becomes less.
D. The pH changes only at the equivalence point.
Explanation: Choice C is the best answer, because the log scale means that as long as the concentrations are 100 times different, then the linear difference is 2.0 on the log scale. This in turn means that the slopes are equal through most of the titration, except near the equivalence point. Perhaps the answer would be better if it mentioned the different concentrations of the titrant bases in each trial. The best answer is not always perfect.
Thank you in advance 🙂
I understand why the answer is NOT A, B, or D. But I just do not get what C is even saying, thank you!
41. Even though the NaOH concentration in the third trial is 100 times greater than the NaOH concentration in the first trial, the two graphs follow a similar slope' This is BEST explained by which of the following statements?
Note: The first trial is 25 mL 0.01 M HCI titrated by 0.01 M NaOH
The third trial is 25 mL 1.00 M HCI titrated by 1.00 M NaOH
A. The solution is a buffered solution, so the pH change is minimal.
B. The NaOH is a weak base and does not fully react with the HCl.
C. The pH is a log scale, so as the pH increases up to 7.0, the amount of base necessary to increase the pH becomes less.
D. The pH changes only at the equivalence point.
Explanation: Choice C is the best answer, because the log scale means that as long as the concentrations are 100 times different, then the linear difference is 2.0 on the log scale. This in turn means that the slopes are equal through most of the titration, except near the equivalence point. Perhaps the answer would be better if it mentioned the different concentrations of the titrant bases in each trial. The best answer is not always perfect.
Thank you in advance 🙂