CBSE
Multiple Choice QuestionsLarge difference in boiling points is observed in
N and P
P and As
As and Sb
Sb and Bi
The depression in freezing point of 0.1 M aqueous solutions of HCl, CuSO4 and K2SO4 are in the ratio
1 : 1 : 1.5
1 : 2 : 3
1 : 1 : 1
2 : 4 : 3
Assertion : Azeotropic mixtures are formed only by non-ideal solutions and they may have boiling points either greater than both the components or lesser than both the components.
Reason : The composition of the vapour phase is same as that ofthe liquid phase of an azeotropic mixture.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false
If both assertion and reason are false.
The solubility of a gas in water at 300 K under a pressure of 100 atm is 4 x 10-3 kg L-1. Therefore, the mass of the gas in kg dissolved 250 mL of water under a pressure of 250 atm at 300 K is :
2.5 x 10-3
2.0 x 10-3
1.25 x 10-3
5.0 x 10-3
In countries nearer to polar region, the roads are sprinkled with CaCl2 .This is :
to minimise the wear and tear of the roads
to minimise the snow fall
to minimise pollution
to minimise the accumulation of dust on the road
How many grams of CaC2O4 will dissolve in distilled water to make one litre of saturated solution? Solubility product of CaC2O4 is 2.5 x 10-9 mol2 litre-2 and its molecular weight is 128
0.0640 gm
0.0032 gm
0.0128 gm
0.0064 gm
A 6% solution of urea is isotonic with :
1M solution of glucose
0.05 M solution of glucose
6% solution of glucose
25% solution of glucose
Which of the following pairs of substances cannot exist together in solution?
Na2CO3 + NaOH
NaHCO3 + Na2CO3
NaHCO3 + NaOH
NaOH + HCl
1 g of a non-volatile, non-electrolyte solute of molar mass 250 g/mol was dissolved in 51.2 g of benzene. If the freezing point depression constant , kf of benzene is 5.12 kg K mol-1 , the freezing point of benzene is lowered by :
0.3 K
0.5 K
0.2 K
0.4 K
Arrange the given compounds in decreasing order of boiling points.
I. CH3CH2CH2CH2Br
II. C(CH3)3Br
III. CH3-CH2-CH(CH3)-Br
I > III > II
II > I > III
I > II > III
III > I > II
