Time Left:
600
sec
1. During the formation of a chemical bond between two atoms:
A. Only forces of repulsion are operative
B. Forces of attraction and repulsion forces, both are operative
C. Forces are not involved
D. Only forces of attraction are operative
2. Who discovered the octet rule?
A. Langmuir
B. Debye
C. Boyle
D. Kossel and Lewis
4. A CO2 molecule contains:
A. Two sigma and two pi bonds
B. Four sigma bonds
C. Three sigma and one pi bond
D. Four pi bonds
5. Which one of them is an odd-electron molecule?
A. BCl3
B. SF6
C. NO
D. CO2
6. According to the Lewis symbols, the nucleus as well as the electrons in the inner shell of an element is represented by:
A. The symbol of the element
B. The number of dots on the symbol
C. Atomic mass
D. Atomic number
8. Select the molecule in which the central atom has incomplete octet.
A. NF3
B. BeH2
C. H2O
D. CO2
9. Among the following compounds octet rule is not obeyed by:
A. PCl3
B. SF6
C. SO3
D. SO2
11. The number of dots in the Lewis symbol represents:
A. The number of valence electrons present in the atom
B. Atomic mass of the element
C. Atomic number of the element
D. The electronic configuration of the atom
12. According to Lewis symbol, the valency of N is:
A. 4
B. 3
C. 2
D. 6
13. The formal charge on oxygen which is single bonded in ozone is:
A. -1
B. +1
C. +2
D. -2
14. The formation of a chemical bond is accompanied by:
A. Sometimes increase and sometimes decrease in energy
B. Decrease in energy
C. Increase in energy
D. Neither increase nor decrease in energy
15. Identify an example of covalent solid:
A. Sodium chloride
B. Silicon carbide
C. Calcium chloride
D. Methane
16. Covalent compounds are soluble in:
A. Polar solvents
B. Non-polar solvents
C. Concentrated acids
D. All solvents
17. A force which binds atoms of same or different elements by mutual sharing of electrons is called:
A. Covalent bond
B. Co-ordinate bond
C. Hydrogen bond
D. Ionic bond
18. Which one of the following statement is not true for octet rule?
A. It does not explain relative stability of molecules.
B. It is useful for understanding structures of most of organic compounds.
C. It is based upon the chemical inertness of noble gases.
D. It accounts for the shape of molecules.
19. Among the following molecules octet rule is not obeyed by:
A. OF2
B. CO2
C. PCl3
D. ClF3
20. The number of electrons present in the valence shell of the central atom of super octet molecules is:
A. Six
B. More than eight
C. Eight
D. Two
Submit Test