Qualitative Analysis of Eleven Household Chemicals Experiment
Your assignment is to identify eleven household chemicals by using a qualitative analysis
scheme which you could use to implement a series of experiments to determine the chemical
composition of each of eleven substances. You will be given eleven different chemical
compounds. Each compound is a white solid. You are to perform a series of laboratory tests on
the substances in order to determine the identity of each compound. The results of your tests are
given below.
Calcium sulfate (CaSO4): Insoluble in water; no bubbles when acetic acid added; brownish when
iodine added.
Sodium chloride (NaCl): No precipitate when sodium hydroxide added; colorless when
phenolphthalein added; soluble in water; no visible change when heated in a Bunsen burner
flame; no precipitate when copper sulfate added; insoluble in alcohol; no bubbles when acetic
acid added.
Sodium bicarbonate (NaHCO3): Bubbles when acetic acid added; no precipitate when copper
sulfate added; no precipitate when sodium hydroxide added; soluble in water; colorless when
phenolphthalein added.
Cornstarch: Dark blue-black when iodine added; insoluble in water.
Sucrose (C12H22O11): Solid turns brown when heated in a Bunsen burner flame; no precipitate
when sodium hydroxide added; colorless when phenolphthalein added; soluble in water; no
precipitate when copper sulfate added; insoluble in alcohol; no bubbles when acetic acid added.
Sodium hydroxide (NaOH): Turns pink when phenolphthalein added; no bubbles when acetic
acid added; soluble in water.
Fructose (C6H12O6): Soluble in water; no precipitate when sodium hydroxide added; red-brown
precipitate when copper sulfate added; colorless when phenolphthalein added.
Calcium carbonate (CaCO3): Bubbles when acetic acid added; insoluble in water; brownish
when iodine added.
Magnesium sulfate (MgSO4): Colorless when phenolphthalein added; white precipitate when
sodium hydroxide added; soluble in water.
Boric acid (H3BO3): No precipitate when copper sulfate added; soluble in water; colorless when
phenolphthalein added; soluble in alcohol; no bubbles when acetic acid added; no precipitate
when sodium hydroxide added.
Sodium carbonate (Na2CO3): Pink when phenolphthalein added; bubbles when acetic acid
added; soluble in water.
Descriptions of the Chemical Procedures:
Solubility in Water: Place a pea-sized sample of the substance in a test tube with 5 mL of
water. Shake the test tube vigorously as demonstrated by Mr. Gensits. Save the test tubes with
the soluble test tubes for the phenolphthalein test.
Iodine: Place a small amount of the unknown on a watch glass and add a few drops of iodine to
the sample.
Phenolphthalein: Use the test tubes with the dissolved substances from the water solubility tests.
Add 2 to 3 drops of phenolphthalein to each test tube and mix the solutions.
Sodium Hydroxide (NaOH): Dissolve a small amount of the unknown in water in a test tube.
Add a few drops of sodium hydroxide solution to the test tube.
Copper Sulfate (Benedict’s Solution): Prepare a boiling water bath. Add approximately 2 mL
of Benedict’s solution to a test tube. Add a small sample of the unknown solid to the test tube
and stir. Carefully heat the contents of each tube for 3-5 minutes by placing it in the boiling
water bath. Remove the test tube and note any color change, especially the appearance of a
reddish-brown precipitate.
Acetic Acid: Place a small amount of the solid on a watch glass and add 4 to 5 drops of acetic
acid.
Universal Indicator: Dissolve a pea-sized sample of the substance in a test tube with 5 mL of
water. Add 2 to 3 drops of universal indicator and note its color.
Heating in a Bunsen Burner Flame: Add a small scoop of the solid sample to a dry test tube
and slowly heat the test tube (while holding it at a 45o angle over the flame).
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Names ______________________________
______________________________
______________________________
Date ____________________
Identification of Eleven Household Chemicals Experiment
Report Sheet
Write the name of the chemical that you identified for each of the following unknown
substances:
1
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2
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3
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4
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5
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6
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7
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8
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9
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10
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11
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