1. Which of the following has least covalent P−H bond?

2. Dry ice is

3. Catenation i.e., linking of similar atoms depends on size and electronic configuration of atoms. The tendency of catenation in Group 14 elements follows the order:

4. When excess of Kl is added to copper sulphate solution:

5. If Cl₂ gas is passed in to aqueous solution of Kl containing some CCl₄ and the mixture is shaken then:

6. Red phosphorus is chemically less reactive because

7. Boric acid is an acid because its molecule

8. Which of the following statements regarding ozone is not correct?

9. In the compound of type ECl₃, where E = B, P, As, or Bi, the angle Cl – E – Cl for different E are ion the order:

10. On heating ozone, its volume.

11. Which of the following is the hardest substance known?

12. The element which exists in a liquid state for a wide range of temperatures and can be used for measuring high temperature is

13. Thermodynamically the most stable form of carbon is

14. From B₂H₆ all the following can be prepared except

15. Inert gases such as helium behave like ideal gases over a wide range of temperature .However; they condense into the solid state at very low temperatures. It indicates that at very low temperature there is a

16. Boric acid is polymeric due to

17. In general, the Boron Trihaides act as

18. Ammonia gas can be dried by

19. Graphite is soft solid lubricant extremely difficult to melt. The reason for this anomalous behaviour is that graphite

20. Orthoboric acid when heated to red heat gives