JEE MAIN, AIPMT, Chemistry Question Papers – MCQs Test 28
Sr. No. |
Question |
Answer |
| 1. | Based on the first law of thermodynamics, which one of the following is correct?
(A) For an isochoric process, ΔU = –q (B) For an isochoric process, q = +w (C) For a cyclic process, q = –w (D) For an adiabatic process, ΔU = –w |
Answer: (C) |
| 2. | ΔG0 Vs T plot in the Ellingham’s diagram slopes downwards for the reaction
(A) Mg + (B) 2Ag + (C) C + (D) CO + |
Answer: (C) |
| 3. | α-maltose consists of
(A) two α-D-glucopyranose units with 1-2 glycosidic linkage (B) one α-D-glucopyranose units and one β-D-glucopyranose unit with 1-2 glycosidic linkage (C) two α-D-glucopyranose units with 1-4 glycosidic linkage (D) two β-D-glucopyranose units with 1-4 glycosidic linkage |
Answer: (C) |
| 4. | 0.06 mole of KNO3 solid is added to 100 cm3 of water at 298 k. The enthalpy of KNO3aq solution is 35.8 kJmol–1. After the solute is dissolved the temperature of the solution will be
(A) 293 k (B) 298 k (C) 301 k (D) 304 k |
Answer: (A) |
| 5. | 1 × 10–3 m solution of Pt(NH3)4Cl4 in H2O shows depression in freezing point by 0.0054°C. The structure of the compound will be (Given Kfp(H2O) = 1.860 km–1)
(A) [Pt(NH3)4]Cl4 (B) [Pt(NH3)3Cl]Cl3 (C) [Pt(NH3)2Cl2]Cl2 (D) Pt(NH3)Cl3]Cl |
Answer: (C) |
| 6. | 1.2 g of organic compound on Kjeldahilization liberates ammonia which consumes 30 cm3 of 1 N HCl. The percentage of nitrogen in the organic compound is ______.
(A) 35 (B) 30 (C) 20.8 (D) 46.67 |
Answer: (A) |
| 7. | 50 cm3 of 0.2 N HCl is titrated against 0.1 N NaOH solution. The titration was discontinued after adding 50 cm3 of NaOH. The remaining titration is completed by adding 0.5 N KOH. The volume of KOH required for completing the titration is
(A) 12 cm3 (B) 10 cm3 (C) 21.0 cm3 (D) 16.2 cm3 |
Answer: (B) |
| 8. | 9.65 coulombs of electric current is passed through fused anhydrous MgCl2. The magnesium metal thus obtained is completely converted into a Grignard reagent. The number of moles of Grignard reagent obtained is
(A) 1 × 10–4 (B) 5 × 10–4 (C) 1 × 10–5 (D) 5 × 10–5 |
Answer: (D) |
| 9. | A buffer solution contains 0.1 mole of sodium acetate dissolved in 1000 cm3 of 0.1 M acetic acid. To the above buffer solution, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is ______.
(A) pKa + 1 (B) pKa (C) pKa + Log 2 (D) pKa = Log 2 |
Answer: (C) |
| 10. | A chemical reaction proceeds into the following stepsStep I, 2A Ý X fastStep II, X + B Ý Y slowStep III, Y + B Ý Product fastThe rate law for the overall reaction is
(A) Rate = k[A]2 (B) Rate = k[B]2 (C) Rate = k[A][B] (D) Rate = k[A]2[B] |
Answer: (D) |
| 11. | A mixture of CaCl2 and NaCl weighing 4.44 g is treated with sodium carbonate solution to precipitate all the calcium ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get 0.56 g of CaO. The percentage of NaCl in the mixture is[Atomic mass of Ca = 40]
(A) 75 (B) 31.5 (C) 40.2 (D) 25 |
Answer: (A) |
| 12. |
A plot of In k against (A) (B) (C) (D) R × ΔS° |
Answer: (B) |
| 13. | A radioactive atom  emits two a particles and one b particle successively. The number of neutrons in the nucleus of the product will be
(A) X – 4 – Y (B) X – Y – 5 (C) X – Y – 3 (D) X – Y – 6 |
Answer: (B) |
| 14. | A solution is 0.1 M with respect to Ag+, Ca2+, Mg2+ and AI3+ which will precipitate at lowest concentration of [ ] when solution of Na3PO4 is added?
(A) Ag3PO4(Ksp = 1 × 10–6) (B) Ca3(PO4)2(Ksp = 1 × 10–33) (C) Mg3(PO4)2(Ksp = 1 × 10–24) (D) AIPO4(Ksp = 1 × 10–20) |
Answer: (D) |
| 15. | A solution of two liquids boils at a temperature more than the boiling point of either of them. Hence, the binary solution shows
(A) positive deviation from Raoult’s law (B) negative deviation from Raoult’s law (C) positive or negative deviation from Raoult’s law depending upon the composition (D) no deviation from Raoult’s law |
Answer: (B) |
O2 → MgO
(abscissa) is expected to be a straight line with intercept on ordinate axis equal to
