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What happens if methyl orange was used instead of phenolphthalein in the standardization of NaOH using KHP?
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+ Sodium hydroxide
+ Chemistry
+ Standardization
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Mattie Bush
What happens if methyl orange was used instead of phenolphthalein in the standardization of NaOH using KHP?
Indicator choice is based on the pH of the equivalence point for the acid-base titration you are doing. You should choose an indicator that changes colour at or near the equivvalence point. The titration curve is steep then, and you will get a good end point.
Phenolphthalein changes colour at a pH above 7. So it is quite good as an indicator for titrations of strong acids with strong bases. It is also suitable for titrations of weak acids and strong bases, which have an equivalence point at a pH above 7.
It is not a good choice for a titration between a strong acid and a weak base, as the equivalence point is below a pH of 7. Methyl orange changes colour at a suitable pH.
Indicator choice is based on the pH of the equivalence point for the acid-base titration you are doing. You should choose an indicator that changes colour at or near the equivvalence point. The titration curve is steep then, and you will get a good end point.
Phenolphthalein changes colour at a pH above 7. So it is quite good as an indicator for titrations of strong acids with strong bases. It is also suitable for titrations of weak acids and strong bases, which have an equivalence point at a pH above 7.
It is not a good choice for a titration between a strong acid and a weak base, as the equivalence point is below a pH of 7. Methyl orange changes colour at a suitable pH.
Since weighed quantity of KHP is titrated with NaOH(aq) to go from clear to pink between 8.2 - 10.0, I would expect to put in a smaller volume of the NaOH(aq) with methyl orange. Making the apparent M of NaOH > with methyl orange.
Since weighed quantity of KHP is titrated with NaOH(aq) to go from clear to pink between 8.2 - 10.0, I would expect to put in a smaller volume of the NaOH(aq) with methyl orange. Making the apparent M of NaOH > with methyl orange.
Indicator choice is based on the pH of the equivalence point for the acid-base titration you are doing. You should choose an indicator that changes colour at or near the equivvalence point. The titration curve is steep then, and you will get a good end point.
Phenolphthalein changes colour at a pH above 7. So it is quite good as an indicator for titrations of strong acids with strong bases. It is also suitable for titrations of weak acids and strong bases, which have an equivalence point at a pH above 7.
It is not a good choice for a titration between a strong acid and a weak base, as the equivalence point is below a pH of 7. Methyl orange changes colour at a suitable pH.
Indicator choice is based on the pH of the equivalence point for the acid-base titration you are doing. You should choose an indicator that changes colour at or near the equivvalence point. The titration curve is steep then, and you will get a good end point.
Phenolphthalein changes colour at a pH above 7. So it is quite good as an indicator for titrations of strong acids with strong bases. It is also suitable for titrations of weak acids and strong bases, which have an equivalence point at a pH above 7.
It is not a good choice for a titration between a strong acid and a weak base, as the equivalence point is below a pH of 7. Methyl orange changes colour at a suitable pH.
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Methyl orange (pH indicator)
below pH 3.1 orange
above pH 4.4 yellow
3.1⇌4.4
Since weighed quantity of KHP is titrated with NaOH(aq) to go from clear to pink between 8.2 - 10.0, I would expect to put in a smaller volume of the NaOH(aq) with methyl orange. Making the apparent M of NaOH > with methyl orange.
Methyl orange (pH indicator)
below pH 3.1 orange
above pH 4.4 yellow
3.1⇌4.4
Since weighed quantity of KHP is titrated with NaOH(aq) to go from clear to pink between 8.2 - 10.0, I would expect to put in a smaller volume of the NaOH(aq) with methyl orange. Making the apparent M of NaOH > with methyl orange.
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