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Is methyl orange a bad indicator for strong acid-strong base titration? Can it lead to a misjudging of colour near the end point?
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Kurt Franzen
Is methyl orange a bad indicator for strong acid-strong base titration? Can it lead to a misjudging of colour near the end point?
Phenolpthalein is better in every regard however,
Methyl orange is an acid-base indicator used in quantitative neutralization (titration) because of its clear and distinct color variance at different pH values.
In acidic medium, methyl orange is red, and when basic, it is yellow. At neutral pH, it is orange.
However as a mid-strength acid, it is therefore it’s used usually in titration of acids.
(Methyl orange is not typically used in strong acid-strong base titrations.)
Unlike universal indicators, methyl orange does not have a full spectrum of color change making it have a sharp end point.
In a solution becoming less acidic, methyl orange changes from red to orange and, finally, to yellow—with the reverse process occurring in a solution of increasing acidity.
I doubt this is quantitative experiment. (Where everything is measured to 4 decimals….and grading means if your answer in the third decimal place is off 0.001 from the actual concentration (either direction) to four decimals, you drop a letter grade.
Don’t worry if you confuse red-orange with Orange-red. Everyone does it.
Should be fine unless you suffer from red-green color blindness.
Methyl orange is an acid-base indicator used in quantitative neutralization (titration) because of its clear and distinct color variance at different pH values.
In acidic medium, methyl orange is red, and when basic, it is yellow. At neutral pH, it is orange.
However as a mid-strength acid, it is therefore it’s used usually in titration of acids.
(Methyl orange is not typically used in strong acid-strong base titrations.)
Unlike universal indicators, methyl orange does not have a full spectrum of color change making it have a sharp end point.
In a solution becoming less acidic, methyl orange changes from red to orange and, finally, to yellow—with the reverse process occurring in a solution of increasing acidity.
I doubt this is quantitative experiment. (Where everything is measured to 4 decimals….and grading means if your answer in the third decimal place is off 0.001 from the actual concentration (either direction) to four decimals, you drop a letter grade.
Don’t worry if you confuse red-orange with Orange-red. Everyone does it.
Should be fine unless you suffer from red-green color blindness.
Yes, the colour change is not as precise as phenolphthalein, so Phph is the indicator of choice.
However the colour change of phenolphthalein does not coincide with the equivalence point for a weak base / strong acid whereas methyl orange does. The colour change must lie on the vertical part of the curve.
Yes, the colour change is not as precise as phenolphthalein, so Phph is the indicator of choice.
However the colour change of phenolphthalein does not coincide with the equivalence point for a weak base / strong acid whereas methyl orange does. The colour change must lie on the vertical part of the curve.
Phenolpthalein is better in every regard however,
Methyl orange is an acid-base indicator used in quantitative neutralization (titration) because of its clear and distinct color variance at different pH values.
In acidic medium, methyl orange is red, and when basic, it is yellow. At neutral pH, it is orange.
However as a mid-strength acid, it is therefore it’s used usually in titration of acids.
(Methyl orange is not typically used in strong acid-strong base titrations.)
Unlike universal indicators, methyl orange does not have a full spectrum of color change making it have a sharp end point.
In a solution becoming less acidic, methyl orange changes from red to orange and, finally, to yellow—with the reverse process occurring in a solution of increasing acidity.
I doubt this is quantitative experiment. (Where everything is measured to 4 decimals….and grading means if your answer in the third decimal place is off 0.001 from the actual concentration (either direction) to four decimals, you drop a letter grade.
Don’t worry if you confuse red-orange with Orange-red. Everyone does it.
Should be fine unless you suffer from red-green color blindness.
Phenolpthalein is better in every regard however,
Methyl orange is an acid-base indicator used in quantitative neutralization (titration) because of its clear and distinct color variance at different pH values.
In acidic medium, methyl orange is red, and when basic, it is yellow. At neutral pH, it is orange.
However as a mid-strength acid, it is therefore it’s used usually in titration of acids.
(Methyl orange is not typically used in strong acid-strong base titrations.)
Unlike universal indicators, methyl orange does not have a full spectrum of color change making it have a sharp end point.
In a solution becoming less acidic, methyl orange changes from red to orange and, finally, to yellow—with the reverse process occurring in a solution of increasing acidity.
I doubt this is quantitative experiment. (Where everything is measured to 4 decimals….and grading means if your answer in the third decimal place is off 0.001 from the actual concentration (either direction) to four decimals, you drop a letter grade.
Don’t worry if you confuse red-orange with Orange-red. Everyone does it.
Should be fine unless you suffer from red-green color blindness.
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Yes, the colour change is not as precise as phenolphthalein, so Phph is the indicator of choice.
However the colour change of phenolphthalein does not coincide with the equivalence point for a weak base / strong acid whereas methyl orange does. The colour change must lie on the vertical part of the curve.
See here:
Yes, the colour change is not as precise as phenolphthalein, so Phph is the indicator of choice.
However the colour change of phenolphthalein does not coincide with the equivalence point for a weak base / strong acid whereas methyl orange does. The colour change must lie on the vertical part of the curve.
See here:
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