CHEMISTRY- p,d and f BLOCK PRACTICE PAPER

BY- UTTAM SINGH PAL

1.       Nitrogen exists as diatomic molecule and phosphorus exists as tetra atomic molecule, why?   [2]

2.       Which of two PH₃ and NH₃ is more basic? [1]

3.       Why is N₂ less reactive at room temperature? [1]

4.       Write the reaction of thermal decomposition of sodium azide [NaN₃]. [1]

5.        Determine the  oxidation number of nitrogen in N₂O, NO₂, HNO₃ and NH₃ .  [2]

6.        Why does PCl₃ fume in moisture? [1]

7.        What is the basicity of H₃PO_4. ? [1]

8.        What happens when PCl₅ is heated.  [1]

9.        Ammonia is a good complexing agent, why? [1]

10.      How is presence of SO₂ detected ? [2]

11.        Sea is the greatest source of some halogens. Comment? [1]

12.      Give the reason for cleaning action of chlorine. [2]

13.      How is ammonia manufactured industrially? Explain [3]

14.      Why is dioxygen a gas but sulphur a solid?  [2]

15.      Which aerosols deplete ozone? [1]

16.       Describe the manufacture of sulphuric acid by contanct process. [5]

17.       Why are halogens are coloured? [1]

18.        How many water molecules are involved in coordination in CuSo4. 5H₂O  ? [1]

19.      Why does copper not replace hydrogen from acids?   [1]

20.    Calculate the magnetic moment of manganese in K₄[Mn(NCS)₆]. [2]

21.      What are transition elements?   [1]

22.     Transition metals and their compound generally exhibit a paramagnetic behavior? [1]

23.     The enthalpies of atomization of transition elements are high. [1]

24.     Describe preparation of potassium di chromate  from iron chromite ore? [2]

25.     Compare chemistry of actinoids with that of lanthanoids with reference to   [3]

i.                     Electronic configuration

ii.                    Oxidation state

iii.                  Chemical reactivity