Chemistry
Give a chemical test to distinguish
(a) Ammonium hydroxide and sodium hydroxide.
(b) Zinc chloride and calcium chloride.
Answer
(a) Add copper sulphate solution (CuSO4) to both the solutions. With sodium hydroxide, a pale blue precipitate is formed which is insoluble in excess of sodium hydroxide. With ammonium hydroxide it forms a pale blue precipitate which dissolves in excess of ammonium hydroxide and forms a deep/inky blue solution.
(b) When ammonium hydroxide (NH4OH) is added dropwise to Zinc chloride (ZnCl2), white gelatinous precipitate of zinc hydroxide forms initially. On adding excess NH4OH, the precipitate dissolves, forming a clear solution.
With calcium chloride, no precipitate forms with NH4OH because calcium hydroxide is not precipitated by ammonium hydroxide in cold solution.
Related Questions
(a) Name a drying agent for ammonia.
(b) How is hydrochloric acid prepared from HCl gas?
(c) Give the equations occurring at anode in the extraction of Aluminium.
(d) In the laboratory preparation, what must be added to sodium chloride to obtain HCI gas ?
Define Isomerism'. Give an example (with IUPAC. name) showing Position isomerism.
Name the following:
(a) A gas other than oxygen obtained at the anode during electrolytic reduction of fused alumina (Al2O3).
(b) An alkaline earth metal in period 3 of the periodic table.
(c) The chemical name of the main ore of zinc.
A double bond hydrocarbon X with 2 carbon atoms is bubbled through bromine dissolved in carbon tetrachloride.
(a) Draw the structure of the compound formed.
(b) What is your observation?
(c) Name the compound formed when steam reacts with X.