Density of a 2.05 M solution of acetic acid in water is 1.02 g/mL. The molality of the solution is
2.28 mol kg-1
3.28 mol kg-1
0.44 mol kg-1
1.14 mol kg-1
A.
2.28 mol kg-1
Mass of 1 L solution = 1.02 × 1000 = 1020 gm
Mass of 0.25 moles of CH3COOH = 2.05 × 60 = 123 gm
Mass of solvent (H2O) = 1020 - 123 = 897 gm = 0.897 kg
Molarity =
=
= 2.285 m
The pKa value of (I) 2 - bromo propanoic acid, (II) 2-fluoro propanoic acid, (III) 3 - fluoro propanoic acid, (IV) 3- bromo propanoic acid decreases as
I > III > IV > II
II > IV > III > I
I > IV > III > II
IV > I > III > II
The correct order of electron affinity of oxygen, sulphur, chlorine, fluorine is
S < O < Cl < F
S < O < F < Cl
O < S < F < Cl
O < S < Cl < F
Favourable conditions for the formation of electrovalent bond is that the cation and anion must have, respectively
high ionisation potential and low electron affinity
low ionisation potential and high electron affinity
high ionisation potential and high electron affinity
low ionisation potential and low electron affinity
Consider the following reaction,
(CH3)3CCl + OH- → (CH3)3C-OH + Cl-
If OH- does not take part in slow step, the molecularity and order of the reaction are respectively,
2, 2
2, 1
1, 2
1, 1
Given, H2O (l) → H2O (g); H1 = +43 kJ
H2O (s) → H2O (l); H2 = +6.05 kJ. Calculate the enthalpy of sublimation of ice.
49.75 kJ mol-1
37.65 kJ mol-1
43.7 kJ mol-1
55.23 kJ mol-1
Which of the following pairs will show common ion effect?
Barium chloride + Barium sulphate
Silver cyanide + Potassium nitrite
Ammonium hydroxide + Ammonium chloride
Sodium chloride + Hydrogen chloride