Materials Required: Magnesium ribbon, sulphur powder, tongs, gas jar, litmus paper, etc.
Observation: There is no effect on blue litmus paper, but red litmus paper turns blue when it is dipped in aqueous solution of magnesium oxide.
Conclusion: Magnesium oxide is basic in nature. This means that metal oxides are basic in nature.
Observation: Blue litmus paper turns red in presence of sulphur dioxide.
Conclusion: Non-metallic oxides are acidic in nature.
Materials Required: Test tubes, copper sulphate solution, iron sulphate solution, copper wire, iron nail, corks, test tube stand
Observation: The colour of copper sulphate fades away and iron nail acquires a brown deposit. No change is observed in the test tube which has iron sulphate solution.
Conclusion: Iron displaces copper from copper sulphate solution. But copper is unable to displace iron from iron sulphate solution. This happens because iron is more reactive than copper.
Materials Required: Test tube, water bath, cork, stand, clamp, dilute sulphuric acid, zinc granules
Observation: Effervescence can be seen in test tube. This shows some chemical reaction taking place. Bubbles can be seen coming from water bath; which shows that some gas is evolving.
Check the nature of gas: Bring a burning matchstick near the bubbles. You will observe that the matchstick burns with a pop sound. This indicates that the evolved gas is hydrogen gas.
Conclusion: When a metal reacts with dilute acid, metal salt and hydrogen gas is formed.
REF: All figures on this page are taken from NCERT text book for Class 10 Science
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