Q 1 :

Ice and water are placed in a closed container at a pressure of 1 atm and temperature 273.15 K.                     [2025]

If pressure of the system is increased 2 times, keeping temperature constant then identify correct observation from following:

• Liquid phase disappears completely.

   

• The amount of ice decreases.

   

• The solid phase (ice) disappears completely.

   

• Volume of system increases.

   

Q 2 :

How many of the following statements are incorrect?

I) Sea water freezes at a lower temperature than pure water

II) Boiling point of sea water increases as it evaporates

III) Sea water boils at a lower temperature than fresh water

IV) Density of sea water at STP is same as that of fresh water

V) Half life is 50% of the total time taken for the completion of a reaction.

VI) Collision frequency (Z), which is the number of collisions per second per unit volume, is same as the rate constant of the reaction

VII) A change in the activation energy of a reaction at a particular temperature will result in a proportional change in the rate and rate constant of the reaction at the same temperature.

VIII) All first order reactions are not unimolecular

IX) For a zero order reaction, slope of a plot of $t_{1/2}$ vs initial concentration will be zero.