The entropy change associated with the conversion of 1 kg of ice at 273 K to water vapours at 383 K is :

(Specific heat of water liquid and water vapour are 4.2 kJ K^$$-$$1 kg^$$-$$1 and 2.0 kJ K^$$-$$1 kg^$$-$$1; heat of liquid fusion and vapourisation of water are 334 kJ^$$-$$1 and 2491 kJ kg^$$-$$1, respectively). (log 273 = 2.436, log 373 = 2.572, log 383 = 2.583)

The major product of the following reaction is :

In which of the following process, the bond order has increased and paramagnetic character has charged to diamagnetic ?

Let z₀ be a root of the quadratic equation, x² + x + 1 = 0, If z = 3 + 6iz$$_0^{81}$$ $$-$$ 3iz$$_0^{93}$$, then arg z is equal to :