Analysis of some inorganic and organic

• Part 1

  1. Perform tests on organic liquids A, B and C

  2. Record observations
• Part 2

  1. Perform tests on inorganic solids X, Y and Z

  2. Record observations
• What are the safety precautions ?

  Wear eye protection.

  ● Avoid skin contact with all the chemicals listed, including the ‘unknowns’.

  ● Ammonia solution gives off ammonia gas, which must not be inhaled, especially by anyone with

  a respiratory problem.

  ● Ethanol is flammable.
• Part 1 of the procedure

  1. Take three test tubes and label them A, B and C

  2. Add 10 drops of the corresponding liquid to each test tube

  3. Add a 1 cm depth of bromine water to each test tube

  4. Shake the mixture
• Part 2 of the procedure

  1. Take three test tubes and label them A, B and C

  2. Add 10 drops of the corresponding liquid to each test tube

  3. Add 1 cm3 acidified potassium dichromate to each test tube

  4. Warm the mixture in a 60 °C water bath for 5 minutes
• Part 3 of the procedure

  1. Take three test tubes and label them A, B and C

  2. Add 10 drops of the corresponding liquid to each test tube

  3. Add 1 cm3 of Fehling's solution to each test tube

  4. Warm the mixture in the water bath
• Part 4 of the procedure

  1. Take three test tubes and label them A, B and C

  2. Add 10 drops of the corresponding liquid to each test tube

  3. Add 1 cm3 of ethanol and 1 cm3 of dilute sodium hydroxide solution to each test tube

  4. Warm the mixture in the water bath for five minutes

  5. Acidify each mixture with dilute nitric acid

  6. Add five drops of silver nitrate solution
• Second step of the entire procedure

  Conduct flame tests for each of the three solids.

  2. Take three test tubes and label them X, Y and Z. Add 10 cm3 distilled water to each

  test tube. Dissolve a spatula full of each solid in the corresponding test tube. Divide

  each solution into three portions.

  (a) To the first portion, add 5 cm3 dilute nitric acid followed by 10 drops of silver

  nitrate solution. Then add dilute ammonia solution.

  (b) To the second portion, add 5 cm3 dilute nitric acid followed by 10 drops of barium

  chloride solution.

  (c) To the third portion, add 2 cm3 of chlorine water.
• Why is nitric acid added in the test for halide ions using silver nitrate ?

  To destroy/react with any carbonate ions so that a precipitate of silver carbonate does not form.
• What are the flame test colours for the ions of group 1 and group 2 elements?

  >>>

  A) red

  B) yellow

  C) lilac

  D) red

  E) blue

  F) red

  G)

  H) green

  I) colourless