Which gas used for purifying, air in underground enterprises ?
How do you express the total hardness of water?
Explain the Avogadro?s law
what is the difference between vector and tensor?
Why cooling is produced when a wet ?khus khus? screen is hung on the doors and windows ?
What is Salts ?
What are the uses of Alloy ?
Why does the filament of an electric lamp glow, when current passes through it ?
What is the difference between volumetric solutions and test solutions
What is Evaporation ?
Do all explosions produce carbon dioxide or carbon monoxide?
Difference between Physical and Chemical change ?
What will happen when a big piece of quick lime is dropped in water ?