371.

Which of the following make up an isotonic triad?

• ${}_{32}{}^{78}\mathrm{Ge}, {}_{33}{}^{77}\mathrm{As}, {}_{31}{}^{74}\mathrm{Ga}$

• ${}_{18}{}^{40}\mathrm{Ar}, {}_{19}{}^{40}\mathrm{K}, {}_{20}{}^{40}\mathrm{Ca}$

• ${}_6{}^{14}\mathrm{C}, {}_8{}^{16}\mathrm{O}, {}_7{}^{15}\mathrm{N}$

• ${}_6{}^{13}\mathrm{C}, {}_7{}^{12}\mathrm{C}, {}_7{}^{14}\mathrm{N}$

The statement "the relative lowering of the vapour pressure is equal to the ratio of the moles of the solute to the total number of the moles in the solution" refers to :

• Hess's law

• Dalton's law

• Raoult's law

• Charle's law

Ethylene glycol is added to water as antifreeze. It will :

• decrease the freezing point of water in the winter and increase the boiling point of water in the summer

• only decrease the freezing point of water

• only increase the boiling point of water

• be used for cleaning the radiator in a car

Which of the following 1 : 1 mixture will act as buffer solution ?

• HCl and NaOH

• CH₃COOH and CH₃COONa

• KOH and CH₃COOH

• CH₃COOH and NaCl

Identify the mixture that shows positive deviation from Raoult's law :

• CHCl₃ + (CH₃)₂CO

• (CH₃)₂CO + C₆H₅NH

• CHCl₃ + C₆H₆

• (CH₃)₂CO + CS₂

If ΔG for a reaction is negative, you infer that the change is : 

• spontaneous

• non-spontaneous

• reversible

• irreversible

What are the products formed when chlorine is passed through aqueous hypo solution?

• Na₂SO₃ + HCl + S

• Na₂SO₃ + SO₃ + HCl

• Na₂SO₄ + HCl + S

• Na₂SO₄ + HCl + SO₂

The vapour pressure of water at 23°C is 19.8 mm, 0.1 mole of glucose is dissolved in 178.2 g ofwater. What is the vapour pressure (in mm) ofthe resultant solution?

• 19.0

• 19.602

• 19.402

• 19.202

Assertion (A) : The aqueous solution of CH₃COONa is alkaline in nature.

Reason (R) : Acetate ion undergoes anionic hydrolysis.

The correct answer is

• both (A) and (R) are true and (R) is the correct explanation of (A).

• both (A) and (R) are true but (R) is not the correct explanation of (A).

• (A) is true but (R) is not true.

• A) is not true but (R) is true.

During the depression in freezing point experiment, an equilibrium is established between the molecules of

• liquid solvent and solid solvent

• liquid solute and solid solvent

• liquid solute and solid solute

• liquid solvent and solid solute