JEE Advanced Chemistry Questions with Solutions: 15 Most Difficult Questions in Past 10 Years, Download PDF Here

We have provided the previous year JEE Advanced Chemistry question paper. Also, you will find the 14 most difficult questions asked in the past JEE Advanced exam. Check the complete article.

JEE Advanced Chemistry Questions: Chemistry is consider to be most easy paper in JEE Advanced. But sometime tricky questions are asked which might be time consuming. Majority of question in JEE Advanced chemistry paper is based on  p-block, Chemical bonding, Coordination compounds, Electrochemistry, Ionic & Chemical Equilibrium, Electrochemistry & Surface Chemistry, Aldehyde & Ketones, Polymers, and Biomolecules.

To master the question based on these topic intense practice is required. Students can solve previous year question for this. In this article we have provided past year JEE Advanced Chemistry questions. Also some tricky questions are provided here.

15 Most Difficult JEE Advanced Chemistry Questions Asked in Previous 10 Years

Check below the most difficult questions in JEE Advanced chemistry in the past 10 years as analysed by the experts:

Q1: The option(s) with only amphoteric oxides is (are) (JEE Advanced 2020)

1. NO, B₂O, PbO, SnO₂ 
2. Cr₂O₃, CrO, SnO, PbO
3. Cr₂O₃, BeO, SnO, SnO₂
4. ZnO, Al₂O₃, PbO, PbO₂

Ans: C and D

Q2: The 1^st, 2^nd and 3^rd ionization enthalpies I₁, I₂ and I₃, of four atoms with atomic numbers n, n + 1, n + 2 and n + 3 where n < 10 are tabulated below. What is the value of n? (JEE Advanced 2020)

Atomic Number	Ionization Enthalpies (kJ/mol)
	I1	I2	I3
n	1681	3374	6050
n+1	2081	3952	6122
n+2	496	4562	6910
n+3	738	1451	7733

Ans: n=9

Q3: Identify the least stable ion among the following: (JEE Advanced 2022)

1. Li^-
2. Be^-
3. B^-
4. C^-

Ans: B

Q4: identify the correct order of acidic strength of CO₂, CuO, CaO, H₂O (JEE Advanced 2022)

1. CaO < CuO < H₂O < CO₂
2. H₂O < CuO < CaO < CO₂
3. CaO < H₂O < CuO < CO₂
4. H₂O < CO₂ < CaO < CuO

Ans: A

Q5: Among the following, the number of elements showing only one  non-zero oxidation state is: (JEE Advanced 2010)

O, Cl, F, N, P, Sn, Tl, Na, Ti

Ans: 2

Q6: Assuming 2s - 2p mixing is not operative, the paramagnetic species among the following is: (JEE Advanced 2014)

1. Be₂
2. B₂
3. C₂
4. N₂

Ans: C

Q7: If the distribution of the molecular speed of a gas is as per the figure shown below, then the ratio of the most probable, the average and the root mean square speeds, respectively, is: (JEE Advanced 2020)

1. 1 : 1 : 1
2. 1 : 1 : 1.224
3. 1 : 1.128 : 1.224
4. 1 : 1.128 : 1

Ans: B

Q8: 1 mol of a monoatomic real gas satisfies the equation p(V-b) = RT where, b is a constant. The relationship of interatomic potential V(r) and interatomic distance for as is given by: (JEE Advanced 2015)

Ans: C

Q9: The treatment of an aqueous solution of 3.74 g of Cu(NO₃)² with excess Kl results in a brown solution along with the formation of a precipitate. Passing H₂S through this brown solution gives another precipitate X. The amount of X (in g) is ______________ ? (JEE Advanced 2022, paper 1)
[Given: Atomic mass of H = 1, N=14, O = 16, S = 32, K = 39, Cu = 63, I = 127]

Ans: 0.32

Q10: For the given close packed structure of a salt made of cation X and anion Y shown below (ions of only one face are shown for clarity), the packing fraction is approximately: (JEE Advanced 2021, paper 1)

(packing fraction = packing efficiency ÷ 100)

Ans: 0.63

Q11: The boiling point of water in a 0.1 molal silver nitrate solution (solution A) is x°C. To this solution A, an equal volume of 0.1 molal aqueous barium chloride solution is added to make a new solution B. The difference in the boiling points of water in the two solutions A and B is y x 10^-2 °C.

(Assume: Densities of the solutions A and B are the same as that of water and the soluble salts dissociate completely. Use: Molal elevation constant (Ebullioscopic Constant), K = 0.5 K kg mol^-1; Boiling point of pure water as 100°C).

The value of lyl is__________ (JEE Advanced 2021, paper 1)

Ans: 2.5

Q12: In a bimolecular reaction, the steric factor P was experimentally determined to be 4.5. The correct option(s) among the following is(are) (JEE Advanced 2017, paper 2)

1. The activation energy of the reaction is unaffected by the value of the steric factor
2. Experimentally determined value of frequency factor is higher than that predicted by Arrhenius equation
3. Since P= 4.5, the reaction will not proceed unless an effective catalyst is used
4. The value of the frequency factor predicted by the Arrhenius equation is higher than that determined experimentally

Ans: A and B

Q13: The decomposition reaction 2N₂O₅ (g) → 2N₂O₄ (g) + O₂(g) is started in a closed cylinder under Isothermal isochoric condition at an initial pressure of 1 atm. After Y x 10³ s, the pressure inside the cylinder is found to be 1.45 atm. If the rate constant of the reaction is 5 x 10^-4 S^-1, assuming ideal gas behaviour, the value of Y is___________ (JEE Advanced 2019, paper 2)

Ans: 2.30

Q14: Consider a Helium (He) atom that absorbs a photon of wavelength 330 nm. The change in velocity (in cm s^-1) of the He atom after the photon absorption is ______________

(Assume momentum is conserved when photon is absorbed. Use Planck constant = 6.5 X 10^-13 J s, Avogadro number = 6 X 10²³ mol-1, Molar mass of He = 4 m mol^-1) (JEE Advanced 2021)

Ans: 30 cm/s

Q15: The atomic masses of He and Ne are 4 and 20 a.m.u., respectively. The value of the de Broglie wavelength of He gas at -73°C is "M" times that of the de Broglie wavelength of Ne at 727°C. M is - (JEE Advanced 2013)

Ans: 5

Also Read:

• JEE Advanced Syllabus for Chemistry
• JEE Advanced Syllabus for Physics
• JEE Advanced Syllabus for Mathematics

All JEE Advanced Chemistry Questions From Previous Years

Above we curated and provided you the most difficult questions in JEE Advanced Chemistry over the past 10 years. However, candidates who wish to have all the previous year JEE Advanced Chemistry questions for practice, can download the PDF files below:

JEE Advanced Chemistry Questions with Solutions 2024 to 2019:

Check below the JEE Advanced Chemistry questions with solutions PDF:

Year	JEE Advanced Chemistry questions with solutions
2024	Paper 1 -  Download here Paper 2 -  Download here
2023	Paper 1 -  Download here Paper 2 -  Download here
2022	Paper 1 - Download here Paper 2 - Download here
2021	Paper 1 - Download here Paper 2 - Download here
2020	Paper 1 - Download here Paper 2 - Download here
2019	Paper 1 - Download here Paper 2 - Download here

Also Check:

JEE Advanced Physics Questions

JEE Advanced Maths Questions

JEE Advanced Chemistry Section Overview

Check below the details regarding the JEE Advanced Chemistry section in JEE Advanced question paper followed in the past 2 years:

Total Marks in JEE Advanced Chemistry section: 120

• 60 marks in JEE Advanced paper 1
• 60 marks in JEE Advanced paper 2

In each paper of JEE Advanced, the Chemistry section has the following sections:

• Sec-I (Max. marks-12)
• Sec-II (Max. Marks-12)
• Sec-III (Max. marks-24)
• Sec-IV (Max. marks-12)

Number of questions and marks distribution in each of the sections is as follows:

Section	Number of questions and total marks	Marking Scheme
1	4 questions of 12 marks	+3 If ONLY the correct option is chosen 0 If none of the options is chosen (i.e. the question is unanswered) -1 in all other cases
2	3 questions of 12 marks	+4 ONLY if (all) the correct option(s) is(are) chosen +3 If all four options are correct but ONLY three options are chosen +2 If three or more options are correct but ONLY two options are chosen, both of which are correct +1 If two or more options are correct but ONLY one option is chosen and it is a correct option 0 If none of the options is chosen (i.e. the question is unanswered) -2 In all other cases
3	6 questions of 24 marks	+4 for the correct answer 0 for no attempts
4	4 questions of 12 marks	+3 If ONLY the correct option is chosen 0 If none of the options is chosen (i.e. the question is unanswered) -1 for the wrong attempts

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