Due to the steepness of the titration curve of a strong acid around the equivalence point, either indicator will rapidly change color at the equivalence point for the titration of the strong acid. In contrast, the pKin for methyl red 5. In general, for titrations of strong acids with strong bases and vice versa , any indicator with a pK in between about 4.
For the titration of a weak acid, however, the pH at the equivalence point is greater than 7. Conversely, for the titration of a weak base, where the pH at the equivalence point is less than 7. In the titration of a weak acid with a strong base, which indicator would be the best choice? The correct answer is C. In the titration of a weak acid with a strong base, the conjugate base of the weak acid will make the pH at the equivalence point greater than 7.
Therefore, you would want an indicator to change in that pH range. Both methyl orange and bromocresol green change color in an acidic pH range, while phenolphtalein changes in a basic pH. The existence of many different indicators with different colors and pKin values also provides a convenient way to estimate the pH of a solution without using an expensive electronic pH meter and a fragile pH electrode. Indicator colors In a solution that decreases in acidity, methyl orange moves from the colour red to orange and finally to yellow with the opposite occurring for a solution increasing in acidity.
In an acid, it is reddish and in alkali, it is yellow. Methyl orange is a pH indicator frequently used in titrations because of its clear and distinct colour change. Because it changes colour at the pH of a midstrength acid, it is usually used in titrations for acids. If you use phenolphthalein, you would titrate until it just becomes colourless at pH 8. On the other hand, using methyl orange, you would titrate until there is the very first trace of orange in the solution….
Phenolphthalein is a suitable indicator for this titration. Methyl orange is not suitable for this titration because its pH range lies on the flat portion of the curve.
Explanation: Methyl orange and phenolphthalein use as indicator , In Acidic solution Methyl orange gives red colour but in basic solution it gives yellow colour. In Acidic solution phenolphthalein is colourless but in basic it gives pink colour.
Methyl orange gives yellow in basic while phenolphthalein gives pink colour in basic solution.. Methyl orange is a pH indicator frequently used in titrations because of its clear and distinct colour change. Because it changes colour at the pH of a midstrength acid, it is usually used in titrations for acids.
If you use phenolphthalein, you would titrate until it just becomes colourless at pH 8. On the other hand, using methyl orange, you would titrate until there is the very first trace of orange in the solution…. When methyl orange indicator is added to sodium hydroxide a base , It changes its colour from orange to yellow. Methyl orange is used as an indicator with acid, the color of the solution turns red.
When methyl orange is used as an indicator with base, the color of the solution turns yellow. As dilute hydrochloric is acidic in nature, when methyl orange is added to it, the color of the solution turns red. Answer: In a solution becoming less acidic, methyl orange moves from red to orange and finally to yellow with the reverse occurring for a solution increasing in acidity. The entire color change occurs in acidic conditions.
In an acid, it is reddish and in alkali, it is yellow. Explanation: Methyl orange turns red in the acidic solution and yellow in basic solution. Hence, to convert it to the yellow colour, the student needs to add an excess of the basic solution as sodium hydroxide is a strong base, it can change the colour of the solution to yellow. In acidic solution, methyl orange turns into a red colour.
In basic solution, methyl orange turns into a yellow colour. Litmus, phenolphthalein, and methyl orange are all indicators that are commonly used in the laboratory. Litmus indicator solution turns red in acidic solutions, blue in alkaline solutions, and purple in neutral solutions. Litmus paper comes as red litmus paper and blue litmus paper.
The table shows the colour changes it can make:.
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