1. What is the main element found in steel?
2. The gas which cause acid rain in industrial area.
3. The gas helps to ripen fruits:
4. Which gas is essential for combustion?
5. Which of the following materials is the best conductor of Electricity?
6. Which of the following is the best conductor of Electricity?
7. ……………is the purest form of carbon
8. How much part of the iceberg is visible above the surface of water?
9. A light –sensitive compound used in photography is
10. Thin leaves of which metal are used as Ayurvedic
11. Which of the following is used in rockets to burn the fuels?
12. The Noble Gas which is present in microscopic quantities air is………
13. Which of the following is not an explosive?
14. The inert gas obtained as a component of natural hydrocarbon gas is
15. The raw material used in the manufacture of cement is………
Limestone and gypsum
16. Sodium is kept in ……..liquid
17. Mercury is a__________
18. A substance having long chains of similar molecules linked together are called…………
19. The gas used for welding:
20. What metallic element is found in “fool’s gold”?
21. Which of the following gases is used in cigarette lighters?
22. The raw materials from which, rayon is manufactured
23. The term ‘octane number’ is related to…….
24. Which of the following is present in hard water?
25. Freon-12 is used ad