The mass percentage of aspirin (C₉H₈O₄) in acetonitrile (CH₃CN) when 6.5 g of C₉H₈O₄ is dissolved in 450 g of CH₃CN will be:
1. 1.424%
2. 4.424%
3. 5.124%
4. 2.124%

Nalorphene (C₁₉H₂₁NO₃), similar to morphine, is used to combat withdrawal symptoms in narcotic users. The dose of nalorphene generally given is 1.5 mg.

Calculate the mass of 1.5 × 10⁻³m aqueous solution required for the above dose.
1. 13.22 g
2. 3.22 g
3. 11.22 g
4. 9.22 g

The amount of benzoic acid (C₆H₅COOH) required for preparing 250 mL of 0.15 M solution in methanol is:

The depression in the freezing point of water was observed for the same amount of acetic acid, trichloroacetic acid, and trifluoroacetic in the order of-

1. acetic acid < trichloroacetic acid < trifluoroacetic acid

2. acetic acid > trichloroacetic acid > trifluoroacetic acid

3.  acetic acid < trichloroacetic acid > trifluoroacetic acid

4. acetic acid > trichloroacetic acid < trifluoroacetic acid

The depression in the freezing point of water when 10 g of CH₃CH₂CHClCOOH is added to 250 g of water will be:

 (K_a = 1.4 × 10^–3, K_f = 1.86 K kg mol^–1)

1. 0.32 K

2. 2.87 K

3. 0.65 K

4. 5.03 K

When 19.5 g of fluoroacetic acid (CH₂FCOOH) is dissolved in 500 g of water, the observed depression in the freezing point was found to be 1.00 K. The Van’t Hoff factor and the dissociation constant of the fluoroacetic acid, respectively are: (Given: \(K_f\) for water = 1.86 K kg mol⁻¹, Molar mass of CH₂FCOOH = 78 g mol⁻¹)

100 g of liquid A (molar mass 140 g mol^–1) was dissolved in 1000 g of liquid B (molar mass 180 g mol^–1). The vapour pressure of pure liquid B was found to be 500 torr. If the total vapour pressure of the solution is 475 torr, the vapour pressure of pure liquid A will be:

Air consists primarily of nitrogen, which occupies approximately 79% by volume at 298 K under normal conditions. Water is in equilibrium with air at a total pressure of 10 atm and a temperature 298 K. The Henry's law constant for nitrogen in water at 298 K is given as 6.51 × 10⁷ mm Hg.

Determine the mole fraction of dissolved nitrogen in the water under these conditions:

The amount of CaCl₂ (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27 °C is:

If 22 g of benzene is dissolved in 122 g of CCl₄, the mass percentage of CCl₄ and benzene respectively are-

1. $15.28$ $\%,$ $84.\mathrm{72<mspace\; width="1em"></mspace>}\%$ $$

2. $84.72$ $\%,$ $15.28$ $\%$

3. $8.72$ $\%,$ $91.\mathrm{28<mspace\; width="1em"></mspace>}\%$

4. 91.28 %, 8.72 %