Why is it important to not add more than 3 drops of indicator?

If more than 2–3 drops are used, we would need more amount of base to neutralize your indicator. Thus, end point would shift to a slightly higher value. This would make the acid appear more concentrated than it really is.

Why is it important to use a small amount of indicator in a titration?

Indicator is added in small quantity while doing titration as its an easy method of determining concentration of an unknown solution with the help of volumetric titrations, where we take a reference of a solution of known standard to find unknown one.

How does indicator affect concentration?

Acid-base indicators, also known as pH indicators, change color in response to changes in hydrogen ions concentration. In acid-base chemistry, titrations can be used to determine the concentration of an unknown solution.

What happens when you add more phenolphthalein to an acid?

At such a high pH, Phenolphthalein will not impart a pink colour. On adding an acid solution, the concetration of OH- ion decreases and pink colour will appear. In the pH range of 8.3 -10.0, it will impart pink colour.

What happens when you add too much base to an acid?

pH is a measure of the concentration of H3O+ ions in a solution. Adding an acid increases the concentration of H3O+ ions in the solution. An acid and a base are like chemical opposites. If a base is added to an acidic solution, the solution becomes less acidic and moves toward the middle of the pH scale.

Can you have too much indicator?

The indicator itself is either a weak acid or a weak base. Adding too much indicator will force your titration to significantly include the indicator an an interfering analyte component competing with your titrant against the acid or base which you are expecting to measure.

Does indicator affect pH?

Normally, the indicator causes the color of the solution to change depending on the pH. The pH value of a neutral solution is 7.0 at 25°C (standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic (alkaline).

How much indicator should be added to a titration?

You just need enough so that the color is visible once the pH becomes basic enough. If you were titrating a large volume, you might need more than a couple of drops, but 2 drops is enough to be sure that the color will be visible in a typical lab-scale titration vessel. One drop would probably even work.

Does the type of indicator affect titration?

Yes. You have to add water to your titration flask, then add the indicator, then titrate very very carefully, drop by drop, until the indicator changes colour to the colour you are expecting at the end point of your main titration.

Does adding more phenolphthalein indicator affect titration?

Phenolphtalein is slightly acidic. It does affect titration because if you add too much, then it will alter the concentration of whichever solution you are adding it in. If you added it to the acid, it will cause that acid to be more acidic than you may have calculated.

What happens if you choose the wrong indicator in a titration?

In contrast, using the wrong indicator for a titration of a weak acid or a weak base can result in relatively large errors, as illustrated in Figure 17.3. In contrast, methyl red begins to change from red to yellow around pH 5, which is near the midpoint of the acetic acid titration, not the equivalence point.