Experiment 19: Identify bleaching powder
To identify bleaching powder among given samples of chemicals
- Given four samples: bleaching powder; sodium chloride; calcium carbonate; and ammonium chloride
- dil. sulphuric acid
- flowers petals
- test tubes
- Put the arnd 1g of salts in different test tubes (marked A, B, C & D) and add 10mL water
- Take about 10 mL of dilute sulphuric acid in each of remaining four test tubes. Label them as E, F, G, and H
- Dip a small piece of coloured cloth or flower petal in test tube A
- Take out the cloth or flower petal from the test tube A and dip it in dil. sulphuric acid in test tube E and stir it gently with the help of a glass rod.
- Repeat the process for Test Tube B, C and D
- No change in color observed in 3 petal when inserted in test tubes. However, for one of the test tubes, petal is decolorized
- Sample which decolorizes the flower petal contains bleaching powder
- Bleaching powder is a pale yellowish powder existing with a strong smell of chlorine. It is soluble in water but due to the presence of impurities, we never observe a clear solution. Its chemical formula is CaOCl2 with its chemical name as Calcium hypochlorite.