Equimolar solutions in the same solvent have-
(a) Same boiling point but different freezing point
(b) Same freezing point, but different boiling point
(c) Same boiling and same freezing point
(d) Different boiling and different freezing points
(a) Same boiling point but different freezing point
(b) Same freezing point, but different boiling point
(c) Same boiling and same freezing point
(d) Different boiling and different freezing points
(c) Same boiling and same freezing point
When mercuric iodide is added to the aqueous solution of potassium iodide, the:
(a) Freezing point is raised
(b) Freezing point does not change
(c) Freezing point is lowered
(d) Boiling point does not change
Explain why on addition of 1 mol of NaCl to 1 litre of water, the boiling point of water increases, while addition of 1 mol of methyl alcohol to one litre of water decreases its boiling point.
The molal elevation constant depends upon
(a) nature of solute.
(b) nature of the solvent.
(c) vapour pressure of the solution.
(d) enthalpy change.
Which of the following aqueous solutions containing 10 g of solute in each case, has highest m.p.?
(a) NaCl solution
(b) KCl solution
(c) sugar solution
(d) glucose solution
State Raoult’s law for a solution containing nonvolatile solute. What type of deviation from Raoult’s law is shown by a solution of chloroform and acetone and why?
Explain the solubility rule “like dissolves like” in terms of intermolecular forces that exist in solutions.
State Raoult’s law for the solution containing volatile components. What is the similarity between Raoult’s law and Henry’s law ?
Which base is present in RNA but not in DNA?
(a) Uracil
(b) Cytosine
(c) Guanine
(d) Thymine
Silver crystallises in f.c.c. Lattice. It edge length of the unit cells is 4.07 × \(10^{–8}\) cm density and ism 10.5g \(cm^{–3}\). Calculate the atomic mass of silver.
(A) 144 g/mol
(B) 125 g/mol
(C) 106.6 g/mol
(D) 213 g/mol
Which of the following statements is not true about the hexagonal close packing?
(A) The coordination number is 12.
(B) It has 74% packing efficiency.
(C) Tetrahedral voids of the second layer are covered by the spheres of the third layer.
(D) In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer.
When Xe reacts with Fluorine in 1:5 ratio at 873 K it forms
a) \(XeF_2\)
b) \(XeF_4\)
c) \(XeF_6\)
d) \(XeOF_4\)
Which of the following factors is not responsible for the denaturation of proteins?
(a) Heat
(b) Charge
(c) pH change
(d) Organic solvents
The electronic configuration of Cu(II) is 3d⁹ whereas that of Cu(I) is 3d¹⁰. Which of the following is correct?
(a) Cu(II) is more stable
(b) Cu(II) is less stable
(c) Cu(I) and Cu(II) are equally stable
(d) Stability of Cu(I) and Cu(II) depends on nature of copper salts
Acetone and carbon disulphide form binary liquid solution showing positive deviation from Raoult’s law. The normal boiling point (Tb) of pure acetone is less than that of pure \(CS_2\). Pick out the
incorrect statement among the following-
(a) Boiling temperature of the mixture is always less than the boiling temperature of acetone
(b) Boiling temperature of Azeotropic mixture is always less than the boiling temperature of acetone
(c) When a small amount of \(CS_2\) (less volatile component) is added to an excess of acetone boiling point
of the resulting mixture increases
(d) A mixture of \(CS_2\) and \(CH_3\)\(COCH_3\) can be completely separated by simple fractional distillation