1. Among the halogen acids, the weakest acid is
a) HI b) HBr c) HCl d) HF.
2. An element is burnt in limited supply of air to give an oxide A, which on treatment with water gives an acid B. Acid B on heating gives acid C which gives yellow precipitate with silver nitrate solution. Oxide A is
a) P2O3 b) SO2 c) CO2 d) NO2.
3. An element which belongs to group 14 is soft in nature, does not react with pure water, but dissolves in water containing dissolved air. Then the element is
a) C b) Ge c) Pb d) Ti.
4. Inert gas used in beacon lights for safety of air navigation is
a) Helium b) Argon c) Neon d) Xenon.
5. The compound used as smoke screen is
a) PCl3 b) PCl5 c) PH3 d) H3PO3
6. The compound used to arrest the bleeding is
a) K2SO4 b) Potash alum c) Al2(SO4)3 d) KI.
7. The compound with garlic odour is
a) P2O3 b) P2O5 c) H3PO3 d) H3PO4
8. The general electronic configuration of carbon family is
a) ns2np2 b) ns2np3 c) ns2np1 d) ns2np4.
9. The lightest gas which is non-inflammable is
a) He b) H2 c) N2 d) Ar
10. The metalloid among the following is
a) Pb b) P c) Ge d) Sn.
11. The noble gases are unreactive because they
a) have same number of electrons b) have an atomicity of one
c) are gases with low density d) have stable electronic configuration
12. The shape of PCl5 is
a) Bipyramidal b) Trigonal bipyramidal c) Linear d) Tetrahedral.
13. The shape of XeF4 is
a) Tetrahedral b) Octahedral c) Square planar d) Pyramidal
14. The toxic element of Boron family is
a) Boron b) Indium c) Thallium d) Gallium.
15. Which of the following does not belong to group 14?
a) C b) Si c) Ga d) Pb
16. Which of the following has the property of etching on glass?
a) HI b) HF c) HBr d) HCl.
17. Which of the following shows negative oxidation state only?