The total number of electrons in all bonding molecular orbitals of $$O_2^{2 - }$$ is ______________.

(Round off to the nearest integer)

3 moles of metal complex with formula Co(en)₂Cl₃ gives 3 moles of silver chloride on treatment with excess of silver nitrate. The secondary valency of Co in the complex is ___________.

(Round off to the nearest integer)

In a solvent 50% of an acid HA dimerizes and the rest dissociates. The van't Hoff factor of the acid is __________ $$\times$$ 10^$$-$$2.

(Round off to the nearest integer)

The dihedral angle in staggered form of Newman projection of 1, 1, 1-Trichloro ethane is ___________ degree. (Round off to the nearest integer)