Power of Buffers
A pH Meter is a scientific instrument that measures the hydrogen-ion concentration (or pH) in a solution, indicating its acidity or alkalinity. Knowledge of pH is useful or critical in laboratory work. pH meters of various types and quality can be used for soil measurements in agriculture; water quality for water supply systems, swimming pools, etc.; brewing, industrially or domestically; healthcare, to ensure that solutions are safe when applied to patients and many other applications.
In this laboratory experiment, your students will be introduced to the concept of buffers. Students will slowly add an acid or base to the buffer solution and first determine which of the solutions is a buffer. Finally, once the student group has determined the buffer, they will then calculate the buffer capacity.
PRODUCT INFO
This U-PIK will include enough materials and supplies for eight student groups. Suggested group size is 2-3 students. The U-PIK will include the following:
- 8 LabQuest 2 interfaces
- 8 pH Sensors
- 8 Boxes of Kimwipes
- 8 Magnetic stirrers w/magnets
- 8 DI Wash bottles
- 9 250-mL beakers
- 8 Ring stands
- 9 25-mL Graduated cylinders
- 9 50-mL burettes
- 8 Burette clamps
- 9 Sets of Solutions "A" and "B"
- 9 Bottles of Sodium hydroxide
- 9 Bottles of Hydrochloric acid
- 8 Electrode supports
WHEN TO INTEGRATE?
The pH sensor can easily be used to support the concept of acids and bases. This particular lab will also include an activity centered around the concept of buffers. Students should be able to add various amounts of acid or base to a pre-made buffer solution and monitor the changes that are associated with the aliquots. To maximize the learning potential of the experiment, students should be aquainted with the Henderson-Hasselbalch equation (however, this knowledge is not required to complete the laboratory). Due to the background information on the structure and chemical make-up of a buffer solution, the experiment is suited for a high school science classroom.
Time: One laboratory session.
Student Level: INTERMEDIATE (Grades 9-12)
pH Manual
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