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)

For the first order reaction A $$\to$$ 2B, 1 mole of reactant A gives 0.2 moles of B after 100 minutes. The half life of the reaction is __________ min. (Round off to the nearest integer).

[Use : ln 2 = 0.69, ln 10 = 2.3]

Properties of logarithms : ln x^y = y ln x;

$$\ln \left( {{x \over y}} \right) = \ln x - \ln y$$

(Round off to the nearest integer)