Chemistry/Acids and Bases Prep

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Lab Preparation for “ACIDS AND BASES”

Equipment that must be available

24 plastic wells plates (containing 12 large wells each)
1 vial of neutral litmus paper
12 pH colour cards


6 small dropper bottles of each of:

  • bromthymol blue indicator, labeled “Bromthymol blue”
  • methyl red indicator, labeled “Methyl red”
  • phenolphthalein indicator, labeled “Phenolphthalein”
  • universal indicator, labeled “universal indicator”

6 – 100 mL bottles of each of:

  • HCl (0.1 M), labeled “Highly Acidic”
  • NaOH (0.1 M), labeled “Highly Basic”
  • pH 7 buffer, labeled “NEUTRAL”
  • pH 8 buffer, labeled “A”
  • pH 5 buffer, labeled “B”
  • pH 7 buffer, labeled “C”
  • pH 6 buffer, labeled “D”
  • pH 10 buffer, labeled “E”
  • pH 4 buffer, labeled “F”
  • pH 9 buffer, labeled “G”

Check that the following results are obtained when one drop of each indicator (or small piece of litmus) is added to one pipetful (using smallest plastic pipet available) of each liquid to be tested. If these results do not occur, remake the buffer or check its pH.

Indicator pH = 4 pH = 5 pH = 6 pH = 7 pH = 8 pH = 9 pH = 10
Neutral litmus pale pink pale pink pale pink purplish red reddish purple purple purple
Methyl red pink pinkish orange slightly orange yellow yellow yellow yellow yellow
Bromthymol blue yellow yellow slightly greenish yellow green blue blue blue
Phenolphthalein colourless colourless colourless colourless colourless slightly pink pink
Universal Indicator orangish red orange yellow yellowish green green blue bluish purple