Chemical Reactions PDF - Observations

Lesson 6: Chemical Reactions Q. State your observation 1. Zinc is added to dilute sulphuric acid = A colourless odourless gas is evolved which extinguishes a burning splinter with a pop sound 2. Zinc is added to dilute HCL acid = A colourless odourless gas which extinguishes a burning splinter...

Lesson 6: Chemical Reactions Q. State your observation 1. Zinc is added to dilute sulphuric acid = A colourless odourless gas is evolved which extinguishes a burning splinter with a pop sound 2. Zinc is added to dilute HCL acid = A colourless odourless gas which extinguishes a burning splinter with a pop sound, which is hydrogen 3. Potassium chlorate is heated = A colourless odourless gas which reignites a glowing splinter is evolved, which is oxygen 4. Sodium sulphate +dilute HCL acid = A colourless gas with a suffocating odour like a burning sulphur is released 5. Iron is added to aqueous copper sulphate (2 OBS) = The blue solution turns green and there is a reddish-brown deposit of copper 6.Hydrogen sulphide gas is passed through aqueous copper sulphate = The blue solution becomes colourless and a black precipitate of copper sulphide is obtained 7. Lead nit rate is strongly heated (3 OBS) = When heated strongly, it decomposes to produce light yellow solid lead monoxide, reddish-brown nitrogen dioxide colourless oxygen gas 8. Silver nitrate solution + NaCl solution = A white precipitate of silver chloride is obtained 9. Silver nitrate solution + dilute HCL acid = A white precipitate of silver chloride is obtained 10. Ferrous sulphate solution + NaOH solution = A dirty green precipitate of ferrous hydroxide is obtained 11. BaCl2 solution + sulphuric acid = A white precipitate of barium sulphate is formed 12. BaCl2 solution + aqueous sodium sulphate = A white precipitate of barium sulphate is obtained 13. Hydrogen Sulphide (g) reacts with Cl gas = Sulphur and hydrogen chloride is obtained 14. NH3 (g) reacts with hydrogen chloride (g) = Dense white fumes of ammonium chloride are obtained 15. Na / K + H2O = An explosive reaction occurs, a colour gas which extinguishes a burning splinter with a pop sound 16. Iron is heated with sulphur = Ferrous iron sulphide a black solid is obtained 17. Mercuric oxide is heated = Decomposes into carbon mercury and a colourless odourless gas is released which reignites a glowing splinter 18. Potassium nitrate is heated = A colourless odourless gas which reignites a glowing splinter, which is oxygen 19. Calcium carbonate is heated = A colourless odourless has turns lime water milky is released which is carbon dioxide 20. Copper hydroxide heated = The blue solid changes to black copper oxide 21. Copper carbonate is heated = Greenish blue solid changes to black copper oxide. A colourless odourless gas which turns lime water milky is released which is carbon dioxide 22. Hydrogen peroxide is heated = A colourless odourless gas which reignites a glowing splinter is evolved which is oxygen 23. Zinc is added to aqueous copper sulphate = The blue solution turns colourless and reddish brown deposit of copper is obtained 24. Copper sulphate solution is added to sodium hydroxide solution = A blue precipitate of copper hydroxide is obtained 25. Lead nitrate solution is added to ammonium hydroxide =A white precipitate of lead hydroxide is obtained 26.Calcuim chloride solution is added to sodium hydroxide solution = A white precipitate of calcium hydrozide is obtained 27.Copper is added to silver nitrate solution =The colourless solution turns blue and there is a deposit of silver 28.Copper sulphate crystals are heated =Blue crystalline salt changes to white coloured powder