# Acid-base titration concept questions and answers

1. What is an acid-base titration?

An acid-base titration is a quantitative analysis of acids and bases; it’s a technique used to determine the concentration of an unknown acid or base solution by neutralizing it with a solution of known concentration.

2. What is the end point of a titration?

The end point of a titration is the point at which the indicator changes color. Ideally, the end point coincides with the equivalence point.

3. What is the equivalence point in a titration?

The equivalence point in a titration is the point at which the amount of titrant added is exactly enough to neutralize the analyte solution. In an acid-base titration, this is when the moles of H⁺ equal the moles of OH⁻.

4. What is a titrant?

A titrant is a solution of known concentration used in a titration. It is added to the analyte solution to react with it and determine its concentration.

5. What is an analyte?

An analyte is a substance whose chemical constituents are being identified and measured. In an acid-base titration, it is the solution of unknown concentration.

6. What is a standard solution?

A standard solution is a solution whose concentration is accurately known. It is often used as the titrant in a titration.

7. What is the purpose of an indicator in a titration?

The purpose of an indicator in a titration is to show when the reaction has reached the equivalence point by changing color.

8. How do you determine the concentration of an unknown solution in a titration?

The concentration of an unknown solution in a titration can be calculated using the formula: Ma x Va = Mb x Vb, where Ma is the molarity of the titrant, Va is the volume of the titrant used, Mb is the molarity of the analyte, and Vb is the volume of the analyte.

9. What are the different types of acid-base titrations?

Different types of acid-base titrations include strong acid-strong base titrations, weak acid-strong base titrations, strong acid-weak base titrations, and weak acid-weak base titrations.

10. What does the shape of a titration curve tell you?

The shape of a titration curve can give information about the strength and concentration of the acid and base. The equivalence point can be found at the inflection point of the curve, and the pH at this point can indicate whether the solution is acidic, basic, or neutral.

1. What is a back titration?

A back titration is a titration method where the amount of an analyte is determined by reacting it with a known amount of excess reagent. The remaining excess reagent is then titrated with another, second reagent.

1. What is a primary standard?

A primary standard is a highly pure, stable compound that can be used to accurately determine the concentration of a solution. It has a known amount of reactant and it is often used to prepare a standard solution.

1. What is the role of a buffer in a titration?

In a titration, a buffer solution can be used to maintain the pH at a nearly constant value. This is particularly useful in acid-base titrations where the pH changes can be abrupt.

1. What happens if you overshoot the end point in a titration?

If you overshoot the end point in a titration, the titration will yield a higher volume of titrant than needed to reach the equivalence point, which can lead to inaccurate results.

1. How does the choice of indicator affect the results of a titration?

The choice of indicator can significantly affect the results of a titration. The indicator must change color at a pH close to the equivalence point of the titration to ensure accurate results.

1. What are some common indicators used in acid-base titrations?

Some common indicators used in acid-base titrations include phenolphthalein, bromothymol blue, and methyl orange. Each has a different pH range in which it changes color.

1. What is a phenolphthalein indicator?

Phenolphthalein is a common indicator in acid-base titrations. It is colorless in acidic solution and turns pink in basic solution. The pH range over which it changes color is about 8.2 to 10.0.

1. Why is it important to rinse the burette with the titrant solution before starting a titration?

Rinsing the burette with the titrant solution ensures that any water or other chemicals that may be clinging to the sides of the burette are washed out. This improves the accuracy of the titration results.

1. How can a titration be used in everyday life?

Titration is used in a variety of industries, including food and beverage, pharmaceuticals, and water treatment, to ensure product quality. For example, it’s used to determine the acidity of wine and the amount of ascorbic acid in a vitamin C tablet.

1. What is a titration curve and what does it represent?

A titration curve is a graph of pH versus the volume of titrant added during a titration. The curve represents how the pH changes as we add titrant and it allows us to determine the equivalence point and pKa value of the system.