Acids and Bases Lab
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Scientific Thinking Standard I: Understand the processes of scientific investigations and use inquiry and scientific ways of observing, experimenting, predicting, and validating to think critically.
Performance Standard: Students will use graphic representations (e.g., charts, graphs, tables, labeled diagrams) to present data and produce explanations for investigations.
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Demonstration: The teacher will review acids and bases. She will demonstrate the use of pH test strips to show acidity and alkalinity of known substances, such as vinegar, flavored water and skim milk. She will then show them the various substances that have been placed on stations in the classroom. Each student will have a partner with whom to work.
Hypothesis: We hypothesize that the substances will be: _____________________________________________________________________________________.
Activity: In this activity, students will test various substances for acidity or alkalinity.
Materials: Student-pairs will receive a worksheet to record all data; all other materials will be at each testing station.
Safety Considerations: Students should wear goggles and gloves; there must be no ingestion of liquids; use care when testing known and unknown liquids; use care not to spill substances; report any accidents to the teacher.
Procedure:
1. Students will receive a data sheet to record their pH values.
2. Testing substances and pH test strips will be found in four stations situated in the classroom.
3. Each substance will be labeled as to what it is..
4. Students will circulate to each station, and choose only one substance to test.
5. The worksheet must be completed.
6. There will be a pH scale posted at each station with pH values from 1-14 (see below).
7. At the end of the activity, each pair will write an analysis of what they learned and whether their hypothesis was correct.
pH Scale
Scientific Thinking Standard I: Understand the processes of scientific investigations and use inquiry and scientific ways of observing, experimenting, predicting, and validating to think critically.
Performance Standard: Students will use graphic representations (e.g., charts, graphs, tables, labeled diagrams) to present data and produce explanations for investigations.
______________________________________________________________________________________________________________________________________
Demonstration: The teacher will review acids and bases. She will demonstrate the use of pH test strips to show acidity and alkalinity of known substances, such as vinegar, flavored water and skim milk. She will then show them the various substances that have been placed on stations in the classroom. Each student will have a partner with whom to work.
Hypothesis: We hypothesize that the substances will be: _____________________________________________________________________________________.
Activity: In this activity, students will test various substances for acidity or alkalinity.
Materials: Student-pairs will receive a worksheet to record all data; all other materials will be at each testing station.
Safety Considerations: Students should wear goggles and gloves; there must be no ingestion of liquids; use care when testing known and unknown liquids; use care not to spill substances; report any accidents to the teacher.
Procedure:
1. Students will receive a data sheet to record their pH values.
2. Testing substances and pH test strips will be found in four stations situated in the classroom.
3. Each substance will be labeled as to what it is..
4. Students will circulate to each station, and choose only one substance to test.
5. The worksheet must be completed.
6. There will be a pH scale posted at each station with pH values from 1-14 (see below).
7. At the end of the activity, each pair will write an analysis of what they learned and whether their hypothesis was correct.
pH Scale
Student Data Sheet:
Acids
and Bases |
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Station |
Substance
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pH |
Acid |
Base |
Neutral |
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Stations (Choose only one item to test at each station)
Station 1: Tap water, coca cola, Windex glass cleaner and black coffee
Station 2: Hand soap, spring water, lemon juice and herbal tea
Station 3: Salt water, milk, tomato juice and ginger ale
Station 4: Orange juice, shampoo, baking soda in water and oven cleaner
Effective Questions:
1. Why is it important to have knowledge about acids and bases?
_________________________________________________________________________________________________________________________________.
2. Of the substances at each of the lab stations, are there more acidic or basic substances? Can you name them?
________________________________________________________________________________________________________________________________.
Analyze and Conclude: On the lines below, write 2-3 sentences about what you learned by performing this experiment. Was your hypothesis correct? Why or why not?
________________________________________________________________________________________________________________________________.
(Abundant Health Center, 2013)
Station 1: Tap water, coca cola, Windex glass cleaner and black coffee
Station 2: Hand soap, spring water, lemon juice and herbal tea
Station 3: Salt water, milk, tomato juice and ginger ale
Station 4: Orange juice, shampoo, baking soda in water and oven cleaner
Effective Questions:
1. Why is it important to have knowledge about acids and bases?
_________________________________________________________________________________________________________________________________.
2. Of the substances at each of the lab stations, are there more acidic or basic substances? Can you name them?
________________________________________________________________________________________________________________________________.
Analyze and Conclude: On the lines below, write 2-3 sentences about what you learned by performing this experiment. Was your hypothesis correct? Why or why not?
________________________________________________________________________________________________________________________________.
(Abundant Health Center, 2013)