In upper layer of atmosphere ozone is formed
1). the action of ultraviolet rays on oxygen
2). the combination of oxygen molecules
3). subjecting oxygen to high pressure
4). the action of nitrogen on oxygen in atmosphere
1. Gypsum is used for improvement of:
2. Who discovered the atom bomb?
3. Byproduct obtained by soap industry is
4. Which one of the following is an example of a gel ?
5. Which of the following could be used as fuel in propellant or rockets ?
6. The gas used for artificial fruit ripening of green fruit is
8. The particle required to continue the chain process of Uranium fission is :
9. Among the fuels given below the one with highest calorific value is
10. Aqueous solution of which of the following is a good conductor of electricity