A solution is prepared by mixing 8.5 g of CH₂Cl₂ and 11.95 g of CHCl₃ . If vapour pressure of CH₂Cl₂ and CHCl₃ at 298 K are 415 and 200 mmHg respectively, the mole fraction of CHCl₃ in vapour form is : (Molar mass of Cl = 35.5 g mol⁻¹)

The rate of a reaction quadruples when the temperature changes from 300 to 310 K. The activation energy of this reaction is :

(Assume activation energy and preexponential factor are independent of temperature; ln 2 = 0.693; R = 8.314 J mol⁻¹ K⁻¹)

The electron in the hydrogen atom undergoes transition from higher orbitals to orbital of radius 211.6 pm. This transition is associated with :

An ideal gas undergoes isothermal expansion at constant pressure. During the process :