3.24 g of Hg(NO₃)₂ (molar mass = 324) dissolved in 1000 g of water constitutes a solution having a freezing point of –0.0558°C while 21.68 g of HgCl₂ (molar mass = 271) in 2000 g of water constitutes a solution with a freezing point of –0.0744°C. The K_f for water is 1.86 $\frac{\text{K\hspace{0.17em}–\hspace{0.17em}Kg}}{\text{Mol}}$. About the state of ionization of these two solids in water it can be inferred that:

(1) Hg(NO₃)₂ and HgCl₂ both are completely ionized

(2) Hg(NO₃)₂ is fully ionized but HgCl₂ is fully unionized

(3) Hg(NO₃)₂ and HgCl₂ both are completely unionized

(4) Hg(NO₃)₂ is fully unionized but HgCl₂ is fully ionized  

Find the concentration of fluoride ions in ppm when a 500 g toothpaste sample contains 0.2 g of fluoride.

(1) 250 ppm

(2) 200 ppm

(3) 400 ppm

(4) 1000 ppm

Amount of NaOH present in 200 ml of 0.5 N solution is 

(1) 40 g

(2) 4 g

(3) 0.4 g

(4) 4.4 g

10.6 g of Na₂CO₃ was exactly neutralised by 100 ml of H₂SO₄ solution. Its normality is

(1) 1 N

(2) 2 N

(3) 1.5 N

(4) 0.5 N

Equal volumes of $0.1\mathrm{M}{\mathrm{AgNO}}_3$ and 0.2 M NaCl are mixed. The concentration of ${\mathrm{NO}}_3^{-}$ ions in the mixture will be 

(1) 0.1 M

(2) 0.05 M

(3) 0.2 M

(4) 0.15 M

If 20 ml of 0.4 N NaOH solution completely neutralises 40 ml of dibasic acid. The molarity of acid solution is

(1) 0.1 M

(2) 0.2 M

(2) 0.3 M

(4) 0.4 M

Calculate the molality of a solution of H₂SO₄ having specific gravity 1.98 g mL⁻¹ and composition 95% (w/v)

(1) 7.412

(2) 8.412

(3) 9.412

(4) 10.412

Find the mole fraction of methanol in a solution containing 16 g of methanol and 90 g of water.

1.  0.90

2.  0.090

3.  0.1

4.  1.9

Lowering in vapour pressure is the highest for:

1. 0.2 m urea

2. 0.1 m glucose

3. 0.1 m MgSO₄

4. 0.1 m BaCl₂

The Vapour pressure of CCl₄ at 25°C is 143 mm Hg. 0.5 g of a non-volatile solute (mol. wt. 65) is dissolved in 100 ml of CCl₄. The vapor pressure of the solution is:

(Density of CCl₄ = 1 .58 g/cm³$)$

1. 141.93 mm Hg

2. 94.39 mm Hg

3. 199.34 mm Hg

4. 143.99 mm Hg