Science & Technology

79. The names of the scientists, Newlands, Mendeleev, and Meyer are associated with the development of A.     atomic structure

73. The maximum number of covalent formed by nitrogen is A.     1    B.     2 C.     3    D.

67. The half life period of an isotope is 2 hours. After 6 hours what fraction of the initial quantity

61. The most important ore of aluminium is A.     bauxite    B.     magnetite C.     haematite    D.     monazite

55. The metal does not give H2 on treatment with dilute HCL is A.     Zn    B.     Fe C.

43. The method that cannot be used for removing permanent hardness of water is A.     adding sodium carbonate B.

49. The high reactivity of fluorine is due to A. its high electro negativity B. small size of fluorine atom

43. The method that cannot be used for removing permanent hardness of water is A.     adding sodium carbonate B.

37. The gas used in the manufacture of vanaspati from vegetable oil is A.     hydrogen    B.     oxygen C.

31. The number of waves in n x 10th Bohr’s orbit are A.     n2 B.     n C.   

25. The main use of salt in the diet is to A.     make the taste of food better B.

13. The nucleus of a hydrogen atom consists of A.     1 proton only B.     1 proton + 2

19. The most abundant rare gas in the atmosphere is A. He B. Ne C. Ar D. Xe Answer &

13. The nucleus of a hydrogen atom consists of A.     1 proton only B.     1 proton + 2

7. The molecules of which gas have highest speed? A.     H2 at -73oC B.     CH4 at 300 K

1. The nucleus of an atom consists of A.     electrons and neutrons B.     electrons and protons C.   

79. An aeroplane is flying horizontally with a velocity of 600 km/h and at a height of 1960 m. When