Who suggested that most of the mass of the atom is located in the nucleus? 

Night blindness is cause by lack of which vitamin?

What is the chemical composition of Red Lead? 

Which animal never drinks water in its entire life?  

Whose pieces are the magnet protectors? 

Which one among the following nontoxic gases helps in formation of enzymes which ripen fruit?

The metal always found in free state is__

Who Invented Induction Coil?