The correct statement regarding a solution of two components A and B exhibiting positive deviation from ideal behaviour is :

1.	Intermolecular attractive force between A-A and B-B are stronger than those between A-B
2.	∆mixH = 0 at constant T and P
3.	∆mixV = 0 at constant T and P
4.	Intermolecular attractive forces between A-A and B-B are equal to those between A-B

A 500 g toothpaste sample has 0.4 g fluoride concentration. The fluoride concentration in terms of ppm will be -

Boiling of dil. HCl acid does not increase its concentration beyond 22.2 per cent because hydrochloric acid:

(1) is very volatile

(2) is extremely soluble in water

(3) forms a constant boiling mixture

(4) forms a saturated solution at this concentration

If the relative decrease in vapour pressure is 0.4 for a solution containing 1 mol NaCl in 3 mol of ${\mathrm{H}}_2\mathrm{O}$, then percentage ionisation of NaCl will be -

1. 60%

2. 80%

3. 40%

4. 100%

The Henry's law constant for the solubility of N₂ gas in water at 298 K is 1.0 × 10⁵ atm. The mole fraction of N₂ in air is 0.8. The number of moles of N₂ formed from air dissolved in 10 moles of water at 298 K and 5 atm pressure is-

17.4 % (w/v) ${\mathrm{K}}_2{\mathrm{SO}}_4$ solution at 27 $°$C is isotonic to 5.85 % (w/V) NaCl solution at 27 $°$C. lf NaCl is 100 % ionised, the % ionisation of ${\mathrm{K}}_2{\mathrm{SO}}_4$ in aqueous solution is-

[At wt. of K = 39, Na = 23] :-

1. 25 %

2. 75 %

3. 50 %

4. None of the above

${\mathrm{C}}_6{\mathrm{H}}_6$ freezes at 5.5$°$C. At what temperature will a solution of 10.44 g of ${\mathrm{C}}_4{\mathrm{H}}_{10}$ in 200 g of ${\mathrm{C}}_6{\mathrm{H}}_6$ freeze ? K_f (${\mathrm{C}}_6{\mathrm{H}}_6$) = 5.12$°$C/m

1. 4.60$°$C

2. 0.89$°$C

3. 5.50$°$C

4. None of the above

The vapour pressures of pure benzene and toluene are 160 torr and 60 torr, respectively. The mole fraction of toluene in the vapour phase in contact with an equimolar solution of benzene and toluene will be:

1. 0.50

2. 0.6

3. 0.27

4. 0.73

Which of the following mixtures forms the maximum boiling azeotrope?

During osmosis, the flow of water through a semi-permeable membrane is: