Why is fire extinguished by soda bicarbonate ?
Because soda bicarbonate absorbs all the oxygen of the air surrounding the fire.
Because soda bicarbonate has a cooling effect.
Because soda bicarbonate decomposes to give out carbon dioxide.
Because soda bicarbonate isolates the fire from the sorrounding air.
What happens to iron when it rusts ?
Iron becomes iron nitrate which is rust.
Iron reacts with oxygen of the air to form iron oxide which is rust.
Iron reacts with carbon dioxide to form iron carbonate which is rust.
It becomes lighter.
Why doe3 radio reception improve after sunset ?
Because the temperature of the atmosphere is lowered and the radio waves travel faster at lower temperature.
Becauie, after sunset, there is less electrical. disturbance in the atmosphere.
Because, after sunset, the atmospheric pressure becomes less.
Because, after sunset, there are less dust particles in theatmosphere.
Which planet is closest to the earth ?
Which is the heaviest known metal on earth ?
What is the main constituent of the sun ?
What is the quantity of fresh, air required for a man ?
500 cubic feet of air every 10 minutes.
500 cubic feet of air every 20 minutes.
1000 cubic feet of air every 10 minutes.
1000 cubic feet of air every 20 minutes.
Which of the following statements is incorrect about ultra-sonics ?
These are sounds whose frequencies are higher than 20,000 cycles per second.
These are inaudible to the human ear.
Bats produce ultra-sonic sounds.
Ultra-sonic sounds are produced when ultra-violet light is incident on sea-water.
Why rain water is soft but river water is hard ?
Because rain water is free from chemical impufities and river water contains carbonates and chlorides of magnesium and calcium.
Because rain water contains carbonates and chlorides of magnesium and calcium while the river water is freeftom all chemical impurities.
Because rain water contains carbonates of magnesium while the river water contains chlorides of calcium.
Because rain water contains chlorides of magnesium while the river water contains sulphates of calcium.
Why do we not see stars in the day light ?
Because of the powerful light of the sun.
Because stars do not emit any )ight in day time.
Because stars are hidden by the sun.
Because stars are hidden by the clouds.
1. World Geography -Test-01
2. World Geography -Test-02
3. World Geography -Test-03
4. Geography of India -Test-01
5. Geography of India -Test-02
6. Geography of India -Test-03
7. Geography of India -Test-04
8. Geography of India -Test-05
9. History of India - Test - 01
10. History of India - Test - 02
11. History of India - Test - 03
12. History of India - Test - 04
13. History of India - Test - 05
14. History of India - Test - 06
15. History of India - Test - 07
Phenomena worth travelling
Creepiest Clouds On Earth
Must Have iPhone Accessories
Richest Tennis Players in the world
Benefits of Cucumber
Simple Tips To Living Longer
Tips to get ready for Long Drive
If you are using a GPS ensure you have the latest map update before you depart. It is also worthwhile to purchase a large hardcopy map to enable a bigger picture view of your trip.