Name: Date:
Student Exploration: Titration
Vocabulary: acid, analyte, base, dissociate, equivalence point, indicator, litmus paper,
molarity, neutralize, pH, strong acid, strong base, titrant, titration, titration curve,
weak acid, weak base
Prior Knowledge Questions (Do these BEFORE using the
Gizmo.) There are several definitions of acids and bases.
According to the Brønsted-Lowry definition, an acid is a
substance that is capable of donating a proton to another
substance. A base is a substance that accepts protons.
When an acid and a base are combined, the acid is
neutralized as the base accepts the protons produced by the
acid.
One way to determine if a solution is acidic or basic is to use litmus paper, as shown
above. There are two types of litmus papers: red and blue.
How does litmus paper indicate an acid? Turn Pink
How does litmus paper indicate a neutral substance? Stays Clear
How does litmus paper indicate a base? Turn Blue
Gizmo Warm-up
Litmus is an example of an indicator, a substance that
changes color depending on its pH (pH is a measure of the
concentration of protons, or H+ ions). In the Titration Gizmo™,
you will use indicators to show how acids are neutralized by
bases, and vice versa.
To begin, check that 1.00 M NaOH is selected for the Burette,
Mystery HBr is selected for the Flask, and Bromthymol blue is
selected for the Indicator.
1. Look at the flask. What is the color of the bromthymol blue indicator? Yellow
2. What does this tell you about the pH of the solution in the flask? Slightly
Acidic Solutions with a pH below 7.0 are acidic, while those with a pH
above 7.0 are basic.
3. Move the slider on the burette to the top to add about 25 mL of NaOH to the
, flask. What happens, and what does this tell you about the pH of the flask?
The color is becoming darker, the pH is increasing
Student Exploration: Titration
Vocabulary: acid, analyte, base, dissociate, equivalence point, indicator, litmus paper,
molarity, neutralize, pH, strong acid, strong base, titrant, titration, titration curve,
weak acid, weak base
Prior Knowledge Questions (Do these BEFORE using the
Gizmo.) There are several definitions of acids and bases.
According to the Brønsted-Lowry definition, an acid is a
substance that is capable of donating a proton to another
substance. A base is a substance that accepts protons.
When an acid and a base are combined, the acid is
neutralized as the base accepts the protons produced by the
acid.
One way to determine if a solution is acidic or basic is to use litmus paper, as shown
above. There are two types of litmus papers: red and blue.
How does litmus paper indicate an acid? Turn Pink
How does litmus paper indicate a neutral substance? Stays Clear
How does litmus paper indicate a base? Turn Blue
Gizmo Warm-up
Litmus is an example of an indicator, a substance that
changes color depending on its pH (pH is a measure of the
concentration of protons, or H+ ions). In the Titration Gizmo™,
you will use indicators to show how acids are neutralized by
bases, and vice versa.
To begin, check that 1.00 M NaOH is selected for the Burette,
Mystery HBr is selected for the Flask, and Bromthymol blue is
selected for the Indicator.
1. Look at the flask. What is the color of the bromthymol blue indicator? Yellow
2. What does this tell you about the pH of the solution in the flask? Slightly
Acidic Solutions with a pH below 7.0 are acidic, while those with a pH
above 7.0 are basic.
3. Move the slider on the burette to the top to add about 25 mL of NaOH to the
, flask. What happens, and what does this tell you about the pH of the flask?
The color is becoming darker, the pH is increasing