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Acid and Base Testing 2
Task with Student Directions
Contributed by: New York State Education Department (NYSED)

Task: At this station, you will experiment to determine which of three solutions is acidic and which is basic.

Materials:

  • Solution filled dropper bottles labeled A, B, and C
  • Dropper bottle with phenolphthalein
  • Blue litmus paper
  • Red litmus paper
  • Reaction transparency or plate
  • Waste cup
  • Paper towels
  • Safety goggles
  • Water for cleaning

Background:

Phenolphthalein turns pink in a basic solution.
Blue litmus paper turns red (pink) when dipped in an acidic solution.
Red litmus paper turns blue (purple) when dipped in a basic solution.

Directions:

  1. Put your safety goggles on.
  2. Think carefully about an experiment you could do to determine which of the three solutions is acidic and which is basic.
  3. In the space below, describe the procedures you will follow in conducting your experiment.

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    __________________________________________________________________________

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  4. CARRY OUT YOUR EXPERIMENT.

  5. Record your color observations in the data table below.

Indicator Solution A Solution B Solution C
Blue Litmus      
Red Litmus      
Phenolphthalein      

  1. Wash the reaction plate or transparency with water. Throw away any garbage into the waste cup.

  2. Using the data you have collected and the background information, which solution is acidic?

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    In the space below, explain the reason for your answer.

    __________________________________________________________________________

    __________________________________________________________________________

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  3. Using the data you have collected and the background information, which solution is basic?

    __________________________________________________________________________

    In the space below, explain the reason for your answer.

    __________________________________________________________________________

    __________________________________________________________________________

    __________________________________________________________________________

    __________________________________________________________________________

 

 


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