Liquid and Gaseous States
The qualitative sketches I, II and III given below show the variation of surface tension with molar concentration of three different aqueous solutions of KCl, CH3OH and at room temperature. The correct assignment of the sketches is
One mole of a monoatomic real gas satisfies the equation p(V − b) = RT where b is a constant. The relationship of interatomic potential V(r) and interatomic distance r for the gas is given by
The value of d in cm (shown in the figure), as estimated from Graham's Law, is
The experimental value of d is found to be smaller than the estimate obtained using Graham's Law. This is due to
For gaseous state, if most probable speed is denoted by C*, average speed by and mean square speed by C, then for a large number of molecules the ratios of these speeds are :
Assertion Meniscus of a liquid disappears at critical temperature.
Reason Density of a liquid and its gaseous phase become equal at the critical temperature.
To an evacuated vessel with movable piston under external pressure of 1atm, 0.1mol of He and 1.0 mol of an unknown compound (vapour pressure 0.68 atm. At 0oC) are introduced. Considering the ideal gas behaviour, the total volume (in lite) of the gases at 0oC is close to.
The relation between the average kinetic energy (E) of the gas and Urms is
The term that corrects for the attractive forces present in a real gas in the van der Waals equation is
At 400 K, the root mean square (rms) speed of a gas (molecular weight = 40) is equal to the most probable speed of gas ast 60 K. The molecular weight of the gas is
Reason Molecular weight of ammonia is smaller than nitrogen gas.
|(A)||hydrogen gas (P = 200 atm, T = 273K)||(p)||compressibility factor ≠ 1|
|(B)||hydrogen gas (P ∼ 0, T = 273K)||(q)||attractive forces are dominant|
|(C)||CO2 (P = 1 atm, T = 273K)||(r)||PV = nRT|
|(D)||real gas with very large molar volume||(s)||P(V − nb) = nRT|
(a) Determine (I) molecular weight, (II) molar volume, (III) compression factor (Z) of the vapour and (IV) whether attractive or repulsive force is dominant among the gas molecules.
(b) If the vapour behaves ideally at 1000 K, determine the average translational kinetic energy of a molecule.