The mean free path () of a gas sample is given by:
(c) (d) none of these
(b) A derivation for mean free path of gas.
Which is lighter than dry air?
(a) Moist air (b) SO2
(c) Cl2 (d) O2
(a) Molar mass of moist air is lesser than dry air.
The ratio a/b (the terms used in van der Waals' equation) has the unit:
(a) atm lire mol-1 (b) atm dm3 mol-1
(c) dyne cm mol-1 (d) all of these
(d) The units of 'a; are: atm litre2 mol-2
= atm dm6mol-2 = dyne cm2mol-2
The units of 'b' are: litre mol-1 = dm3mol-1 = cm3mol-1
In the vander Waals' equation, the constant 'a' and 'b' with temperature shows which trend:
(a) both remains same
(b) 'a' remains same, 'b' varies
(c) 'a' varies, 'b' remains same
(d) both varies
(d) This is one of the limitation of vander Waal's equation.
'a' is measure of force, which is sensitive for distance, with increase in temp, the distance between molecule increase,so magnitude of force decrease. 'b' is measure of size, which is not so sensitive as 'a' . but it also changes.
At relatively high pressure, van der Waals' equation reduces to:
(a) PV = RT
(b) PV = RT + a/v
(c) PV = RT + Pb
(d) PV = RT - a/V2
(c) At high pressure, volume of molecules should not be neglected in comoparison to volume of gas. Also experimental to volume of gas. Also experimental studies reveals PV > RT at high P.
When is the deviation more in the behaviour of a gas from the ideal gas equation pV=nRT?
(a) AT high temperature and low pressure
(b) At low temperature and high pressure
(c) At high temperature and high pressure
(d) At low temperature and low pressure
(b) Gases show deviation from ideal gas behaviour when the temperature is low and pressure is high. At low temperature, the volume of one molecule is not negligible in comparison to total volume and intermolecular force of attraction is maximum at low temperature and high pressure.
Joule-Thomson coefficient ()H for an ideal gas is:
(a) zero (b) +ve
(c) -ve (d) none of these
(a) Ideal gas does not show Joule-Thomson effect.
All the three states H2O, i.e., the triple point for H2O the equilibrium,
Ice WaterVapour exist at:
(a) 3.85 mm and 0.0981 C
(b) 4.58 mm and 0.0098 C
(c) 760 mm and 0C
(d) none of the above
(b) The conditions for triple point of H2O.
the particular temperature and pressure at which the solid, liquid, and gaseous phases of a given substance are all at equilibrium with one another.
The unit of van der Waals' constant 'a' is:
(a) atm litre2 mol2 (b) dyne cm4 mol-2
(c) newton m4 mol-2 (d) all of these
(d) a=P x V2 = atm litre2 mol2 = dyne cm4 mol-2 = Newton m4 mol-2 = atm dm6 mol-2
The unit of van der Waals' constant 'b' is :
(a) cm3 mol-1
(b) litre mol-1
(c) m3 mol-1
(d) all of these
(d) b = 4Nv; unit of b = litre mol-1 = cm3 mol-1 = m3 mol-1