Q. Which one of the following is the softest?
1) Iron
2) Lithium
3) Iron
4) Sodium
Q. A balloon filled with helium rises in air because--
1) Helium pushes down on the air below the balloon
2) The balloon is weightless
3) Air exerts an upward force on the balloon
4) Helium is less dense than air
Q. Rusting of iron requires -
1) Oxygen only
2) Oxygen and Carbon dioxide
3) Oxygen and water
4) Carbon dioxide only
Q. Uranium eventually decays into a stable isotope of--
1) Lead
2) Polonium
3) Thorium
4) Radium
Q. Which of the toxic heavy metals is found in modern tannery industries?
1) Nickel
2) Zinc
3) Chromium
4) Lead
Q. Which of the following contains high content of lead?
1) Low octane fuel
2) High octane fuel
3) Cooking gas
4) Coal
Q. Which of the following is not a mixture?
1) LPG
2) Air
3) Gasoline
4) Distilled water
Q. It is an industrial process of producing ammonia by the reaction of nitrogen with hydrogen in the presence of a catalyst:
1) Solvay Process
2) Haber Process
3) Bayer Process
4) Bessemer Process
Q. Stainless steel is an alloy of
1) Iron, Carbon and Nickel
2) Iron and Maganese
3) Iron, Chromium and Zinc
4) Iron, Chromium and Nickel
Q. Which of the following is the Chemical name of the salt we use in our kitchen?
1) Sodium Chloride
2) Ammonium Sulphate
3) Sodium Carbonate
4) Calcium Chloride