Multiple Choice QuestionsWhen 25 g of a non-volatile solute is dissolved in 100 g of water, the vapour pressure is lowered by 2.25 × 10-1 mm. If the vapour pressure of water at 20°C is 17.5 mm, what is the molecular weight of the solute ?
206
302
350
276
A certain mass of a gas occupies a volume of 2L at STP. To what temperature the gas must be heated to double its volume, keeping the pressure constant ?
100 K
273 K
273°C
546°C
The average kinetic energy of one molecule of an ideal gas at 27°C and 1 atm pressure is
900 cal K-1 mol-1
6.21 × 10-21 JK-1 molecule-1
336.7 JK-1 molecule-1
3741.3 JK-1 mol-1
CH4 diffuses two times faster than a gas X. The number of molecules present in 32 g ofgas X is (N is Avogadro number)
N
N/2
N/4
N/16
Under which one of the following conditions do real gases approach the ideal gas behaviour?
Low temperature and high pressure
High temperature and high pressure
High temperature and low pressure
Low temperature and low pressure
Which one of the following is the ratio of the lowering of vapour pressure of 0.1 M , aqueous solutions of BaCl2, NaCl and Al2SO3 respectively?
3 : 2 : 5
5 : 2 : 3
5 : 3 : 2
2 : 3 : 5
Which one of the following equations represents the variation of viscosity coefficient (η) with temperature (T)?
η= Ae-E/RT
η= AeE/RT
η= Ae-E/kT
η= Ae-E/T
Assertion (A): van der Waals' forces are reponsible for chemisorptions.
Reason (R): High temperature is favourable for chemisorptions.
The correct answer is:
(A) is false, but (R) is true
Both (A) and (R) are correct and (R) is the correct explanation of A
Both (A) and (R) are correct and (R) is not the correct explanation of (A)
(A) is true, but (R) is false
Which one of the following is the wrong statement about the liquid?
It has intermolecular force of attraction.
Evaporation of liquids increase with the decrease of surface area.
It resembles a gas near the cnt1cal temperature.
lt is an intermediate state between gaseous and solid state.
Switch
