To show that metals have high melting point.
Materials Required: Copper or aluminium wire, stand, clamp, Bunsen burner
- Fix the copper wire in horizontal position with the help of stand and clamp.
- Fix a nail with the help of wax below the wire at far end.
- Put the Bunsen burner below the wire.
- Heat the wire.
Observation: The metal wire becomes very hot; as can be shown by the falling of nail.
Conclusion: Metals have high melting point.
To show the nature of metallic oxide and non-metallic oxide.
Materials Required: Magnesium ribbon, sulphur powder, tongs, gas jar, litmus paper, etc.
- Hold the magnesium ribbon with tongs, and burn the magnesium ribbon in air.
- Collect the ashes produced on burning the magnesium ribbon.
- Mix the ash in water and test with blue and red litmus paper.
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.
Procedure for Sulphur Powder:
- Take sulphur powder in a China dish, and burn the powder.
- Collect the fumes in a gas jar.
- Introduce wet litmus papers in the gas jar.
Observation: Blue litmus paper turns red in presence of sulphur dioxide.
Conclusion: Non-metallic oxides are acidic in nature.
To show displacement reaction
Materials Required: Test tubes, copper sulphate solution, iron sulphate solution, copper wire, iron nail, corks, test tube stand
- Fill a test tube with copper sulphate solution, and fill another test tube with iron sulphate solution.
- With the help of a thread, suspend the iron nail in test tube which has copper sulphate solution.
- With the help of a thread, suspend the copper wire in test tube which has iron sulphate solution.
- Close the mouth of test tubes with cork, and put test tubes in 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.
To show metal's reaction with dilute acid
Materials Required: Test tube, water bath, cork, stand, clamp, dilute sulphuric acid, zinc granules
- Fix the test tube with stand and clamp. Insert a delivery tube in a cork, and take a water bath.
- Take some zinc granules in the test tube.
- Pour about 5 ml dilute sulphuric acid over zinc granules.
- Just after pouring the acid, close the mouth of the test tube with cork; as shown in the given figure.
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