Identify the correct statements about the anomalous behaviour of Boron I. Boron trihalides can form dimeric structures. II. Boron shows + 1 as stable oxidation state III. Maximum covalency of Boron is four. IV. Boron does not form BF 6 6 - ion.

Step-by-step solution

Due to its smaller size and unavailability of d-electrons boron is found to exhibit properties which are in contrast to the other elements of the boron family. I. Boron trihalides done not form dimeric structures instead they complete octet with back bonding. Other member of this family can form dimeric structures. II. Boron does not show + 1 as stable oxidation state. As we move down this group stability of +1 oxidation state increase. But +1 oxidation state of B is least stable. III. Maximum covalency of Boron is