5. What do you observe when
(a) Co, is passed through lime water first and then a little
in excess
(b) HCl is passed through silver nitrate solution.
(c) HS is passed through lead nitrate solution.
(d) ci, is passed through potassium iodide (KT) solution.
(e) Cobalt chloride paper is introduced in water vapour.
Write balanced equations for each of the above.
Answers
(a) When the gas is passed through lime water, it turns milky due to the formation of a white precipitate of calcium carbonate. The milkiness disappears when CO2 is passed in excess.
(b) Hydrogen chloride gas is passed throughSilver nitrate solution and the product thus form treated with excess of Ammonium hydroxide? A white precipitate of silver chloride will be formed when Hydrogen chloride gas ispassed through silver nitrate.
(c) When H2S is passed through lead nitrate solution, the products are nitric acid and lead sulphide.
(d) When chlorine (Cl2) gas is passed through an aqueous solution of potassium iodide (KI), the products formed are solid iodine (I2) and potassium chloride (KCl). This is a displacement reaction in which the less reactive iodine in potassium iodide is displaced by the more reactive chlorine
(e) Cobalt chloride paper is used to test for the presence of water leaking through tiny cracks in pipes or porcelain. When water is present, the test paper goes from blue to pink. Heat and humidity are two factors that help determine our outdoor comfort level in summer.