when setting up their experiment, a student discovered that the solution in their flask turned bright pink upon adding 2 drops of the indicator, even before beginning the titration. what do you suspect was the mistake that the student made?
I don't know the experiment you are doing but it's probably a titration experiment. The indicator turning pink (assume the indicator was phenolphthalein) means there was base in the flask at the beginning.
Based on the information provided, the bright pink color of the solution before starting the titration indicates that the student likely made an error in the preparation of the solution or in the addition of the indicator. Here are a few possible mistakes the student might have made:
1. Incorrect concentration of the solution: The student might have added too much or too little solute to the solvent, resulting in an incorrect solution concentration. This could cause unexpected reactions with the indicator.
2. Incorrect type of indicator: The student might have used the wrong indicator for the type of titration being conducted. Different indicators are used for different types of reactions (e.g., acid-base, oxidation-reduction) and can produce different colors.
3. Contamination of the solution: The student may have accidentally contaminated the solution or the indicator, leading to an unexpected reaction. For example, if the flask or the dropper used to add the indicator was not clean, it could introduce impurities that affect the color.
4. Reversed order of addition: The student may have added the indicator to the solution before adding the titrant, which could result in an immediate reaction leading to a color change.
To pinpoint the exact mistake, more details about the experiment, such as the purpose, the components used, and the procedure followed by the student, would be necessary.
Based on the information provided, there are a few possibilities for the mistake the student made:
1. Incorrect concentration of the indicator: The student may have used an indicator with a higher concentration than recommended. This could cause a strong, immediate change in color upon adding just a few drops.
2. Contaminated reagents: If the reagents or the indicator solution were contaminated, it could have led to an unexpected color change. Contaminants like impurities or other chemicals could trigger a different reaction.
3. Incorrect flask or equipment selection: It is important to use the right type of flask and appropriate equipment for the experiment. Using a flask that has residual chemicals or a reaction vessel that is not properly cleaned may lead to unwanted color changes.
4. Incorrect procedure or sequence: The student may have mistakenly added the indicator before the solution to be titrated, causing an early color change. The indicator should be added after the solution is ready for titration.
To determine the actual mistake, it is necessary to further investigate the experiment setup, the specific indicator used, and the procedure followed by the student.