Most Repeated Questions in NEET Chemistry are the questions that frequently appear in the exam due to their fundamental importance. The questions are usually from topics like Atomic Structure, Chemical Bonding and Molecular Structure, Thermodynamics, Reaction Mechanisms, Biomolecules & Polymers etc.

The NEET UG exam is scheduled to be conducted on 4th May 2025. A total of 45 questions will be asked from the Chemistry section. Practicing the frequently asked questions in NEET Chemistry will not only provide an idea of the type of questions one can expect in NEET UG 2025 Exam but also increase their chances of getting a good score. Scroll down and get the detailed list of NEET Chemistry most repeated questions.

List of Most Repeated Questions in NEET Chemistry

The candidates can have a look at the list of repeated questions in the NEET Chemistry subject to know the question pattern, list of questions etc in the NEET exam 2025: 

1. For a given reaction, ΔH = 35.5 kJ mol–1 and ΔS = 83.6 JK–1 mol–1. The reaction is spontaneous at: (Assume that ΔH and ΔS do not vary with temperature)

(a) all temperatures
(b) T > 298 K

(c) T < 425 K
(d) T > 425 K
Ans. d

2. Consider the reaction 4NO2 (g) + O2 (g) → 2N2O5 (g) ΔHr = − 111kJ. If N2O5 (s) is formed instead of N2O5 (g) in the above reaction, the ΔHr value will be [Given ΔHsublimation of N2O5 is 54 kJ mol-1]

(a) – 165 kJ
(b) +54 kJ

(c) +219 kJ
(d) – 219 kJ
Ans. d

3. Under the isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is : [Given that 1 L bar = 100 J]

(a) 5 kJ
(b) 25 J

(c) 30 J
(d) – 30 J
Ans. d

4. In which case change in entropy is negative?

(a) Expansion of a gas at constant temperature.

(b) Sublimation of solid to gas

(c) 2H(g) → H2(g)

(d) Evaporation of water
Ans. c

5. The rate constant for a first-order reaction is 4.606×10−3

S−1. The time required to reduce 2.0 g of the reactant to 0.2 g is:

(a) 500 s
(b) 1000 s

(c) 100 s
(d) 200 s
Ans. b

6. For a first-order reaction A → Products, initial the concentration of A is 0.1 M, which becomes 0.001M after 5 minutes. The rate constant for the reaction in min- 1 is

(a) 1.3818
(b) 0.9212

(c) 0.4606
(d) 0.2303
Ans. a

7. Mechanism of a hypothetical reaction X2 + Y2 →→ 2XY is given below 

(a) X2 ⇌⇌ X + X (fast)

(b) X + Y2 →→ XY + Y(slow)

(c) X + Y→→ XY(fast)

The overall order of the reaction will be

(a) 0
(b) 1.5

(c) 1
(d) 2
Ans. d

8. The slope of the Arrhenius plot (ln k v/s 1/T) of a first-order reaction is -5 ⨉ 103 K. The value of Ea of the reaction is. Choose the correct option for your answer. [Given R = 8.314 JK-1 mol-1]

(a) 166 kJ mol-1
(b) – 83 kJ mol-1

(c) 41.5 kJ mol-1
(d) 83.0 kJ mol-1
Ans. b

9. Half-life period of a first-order reaction is 1386

seconds. The specific rate constant of the reaction is:

(a) 5.0 × 10–2s –1
(b) 5.0 × 10–3s –1

(c) 0.5 × 10–2s –1
(d) 0.5 × 10–3s –1
Ans. a

10. If 60% of a first-order reaction was completed in 60 minutes, 50% of the same reaction would be completed in approximately

(a) 45 minutes

(b) 60 minutes

(c) 40 minutes

(d) 50 minutes (log 4 = 0.60, log 5 = 0.69)
Ans.

11. Which of the following has the highest electron affinity?
(a) Fluorine

(b) Oxygen

(c) Chlorine

(d) Nitrogen
Ans. c

12. Which type of hybridization is found in methane (CH₄)?

(a) sp

(b) sp²

(c) sp³

(d) dsp²
Ans. c
13. Which of the following is a strong oxidizing agent?

(a) KMnO₄

(b) NaCl

(c) H₂O₂

(d) NaOH
Ans. a
14. The rate of a chemical reaction increases with temperature because:

(a) Activation energy decreases

(b) More molecules have sufficient energy to react

(c) The entropy of the system increases

(d) The molecular mass of reactants increases
Ans. b
15. Which of the following is an example of a Lewis acid?

(a) NH₃

(b) AlCl₃

(c) H₂O

(d) CH₄
Ans. b
16. What is the IUPAC name of CH₃-CH(OH)-CH₃?

(a) Propanal

(b) Propanol

(c) Propanone

(d) Butanol
Ans. b
17. Which of the following compounds will show tautomerism?

(a) Benzene

(b) Acetone

(c) Ethanol

(d) Phenol
Ans. d
18. The oxidation state of Fe in Fe₂O₃ is:

(a) +2

(b) +3

(c) 0

(d) +4
Ans. b
19. The general electronic configuration of elements in group 17 (halogens) is:

(a) ns² np³

(b) ns² np⁶

(c) ns² np⁵

(d) ns² np⁴
Ans. c
20. The bond angle in water (H₂O) is approximately:

(a) 104.5°

(b) 120°

(c) 180°

(d) 90°
Ans. a

Read More: NEET 2025 Predicted Question Paper

How to Study NEET Chemistry Most Repeated Questions?

To study the NEET Chemistry most repeated questions, the candidates must focus on the following points: 

1. NEET Chemistry Revision Strategy: The candidates must focus on revising the topics they’ve already studied rather than attempting to learn new concepts. Create a revision schedule to cover all the critical concepts.
2. Practice Mock Tests: They must take full-length mock tests regularly to get used to the exam conditions. This will help them improve their time management and get accustomed to the NEET 2025 exam pattern.
3. Analyze Previous Year Papers: They must go through the previous year’s NEET papers and analyze the trends in NEET Chemistry questions. Also, pay attention to topics that frequently appear.
4. Formula Flashcards: Students must create flashcards with essential formulas, equations, and key concepts in NEET Chemistry. Review these flashcards during short breaks to reinforce your memory.
5. Mind Maps: Use mind maps to visualize complex concepts and their interconnections with the topics. Mind maps can help students recall information more effectively.
6. Stay Healthy: Get adequate sleep, eat a balanced diet, and stay hydrated. Preparation before the night before an exam should be avoided. A well-rested mind performs better in exams.
7. Stay Calm: They must manage NEET exam anxiety by practicing relaxation techniques such as deep breathing and meditation. A calm mind can think more clearly during the exam.

Also Read:
Chemistry plays a crucial role in determining the candidate's NEET rank 2025, and solving NEET Chemistry 2025 most asked questions can help students streamline their preparation effectively.