JEE Chemistry 2023 Question with Solution

Given: Five statements about colligative properties, azeotropes, osmosis, density-molarity relation, and AgI sol are to be checked.

Find: Which set of statements is correct.

For (A), elevation in boiling point depends on the van't Hoff factor and concentration:

For $0.1 \, \text{M}$ NaCl, dissociation produces more particles than urea, so the elevation in boiling point is not the same. Hence (A) is incorrect.

For (B), azeotropic mixtures have the same composition in both liquid and vapour phase. Therefore they boil without change in composition. Hence (B) is correct.

For (C), the provided solution marks this statement as correct: osmosis takes place from hypotonic to hypertonic solution. Hence (C) is correct according to the extracted solution working.

For (D), using the relation shown in the solution:

Thus the stated density is approximately $1.26 \, \text{g mL}^{-1}$ for $32\%$ $H_2SO_4$ solution of molarity $4.09 \, \text{M}$. Hence (D) is correct.

For (E), when KI solution is added to silver nitrate solution, the extracted solution states that a positively charged sol is formed due to adsorption of silver ions:

So the statement claiming a negatively charged sol is obtained is incorrect.

Therefore, the correct statements are B, C, and D from the extracted working, but that combination is not present in the options. The solution text itself concludes "B and D only", which matches option D. Hence the most defensible marked answer is D.