Top 50 MCQs for CBSE Class 12 Chemistry Half Yearly Exam 2025

CBSE Class 12 Chemistry: In order to prepare for the CBSE Class 12 Chemistry Half Yearly Exam 2025, one must regularly practice answering objective-style questions in addition to having a solid conceptual grasp. One of the best methods to assess application abilities and conceptual clarity is through multiple-choice questions (MCQs). The Top 50 MCQs for CBSE Class 12 Chemistry have been collected to assist students in efficiently revising. The NCERT syllabus's key chapters are the basis for these questions, which will act as a rapid study aid prior to the test.

CBSE Class 12 Chemistry Exam Pattern 2025-26

Important Instructions for Students:

• Attempt all MCQs carefully before checking the answers.

• Practice solving without referring to textbooks for effective self-assessment.

• The answer key is provided at the end in tabular form for quick reference.

Related: CBSE Class 12 Chemistry Syllabus 2025-26

Top 50 Chemistry MCQs for Class 12 Half Yearly Exam 2025-26

Q1. Which type of solid is diamond?
(a) Molecular solid
(b) Ionic solid
(c) Covalent solid
(d) Metallic solid

Q2. The coordination number of Na+ in NaCl crystal is:
(a) 6
(b) 8
(c) 4
(d) 12

Q3. In Schottky defect:
(a) Equal number of cations and anions are missing
(b) Only cations are missing
(c) Only anions are missing
(d) None of these

Q4. A solution that obeys Raoult’s law is called:
(a) Non-ideal solution
(b) Ideal solution
(c) Azeotropic mixture
(d) Colloidal solution

Q5. Which colligative property is used to determine the molar mass of a solute?
(a) Osmotic pressure
(b) Vapour pressure
(c) Surface tension
(d) Viscosity

Q6. Henry’s law is related to:
(a) Solid in liquid
(b) Gas in liquid
(c) Liquid in liquid
(d) Gas in solid

Q7. The standard reduction potential of hydrogen electrode is:
(a) +1 V
(b) 0 V
(c) –1 V
(d) 2.303 V

Q8. Conductivity of a solution decreases with:
(a) Increase in concentration
(b) Decrease in temperature
(c) Increase in temperature
(d) Increase in dilution

Q9. In a galvanic cell, the flow of current is:
(a) From anode to cathode externally
(b) From cathode to anode externally
(c) From salt bridge to cathode
(d) None of the above

Q10. The unit of rate constant for a first-order reaction is:
(a) mol L⁻¹ s⁻¹
(b) L mol⁻¹ s⁻¹
(c) s⁻¹
(d) No unit

Q11. Which factor does not affect the rate of a reaction?
(a) Temperature
(b) Pressure
(c) Catalyst
(d) Molecularity

Q12. The slope of a straight line obtained by plotting log [R] versus time gives:
(a) Activation energy
(b) Order of reaction
(c) Rate constant
(d) Molecularity

Q13. The process of removing colloidal particles by shaking with electrolyte is called:
(a) Coagulation
(b) Peptization
(c) Dialysis
(d) Electrophoresis

Q14. Tyndall effect is observed in:
(a) True solutions
(b) Colloidal solutions
(c) Suspensions only
(d) Both colloids and suspensions

Q15. Which type of adsorption decreases with increase in temperature?
(a) Chemical adsorption
(b) Physical adsorption
(c) Both (a) and (b)
(d) None

Q16. Which of the following is an ore of aluminium?
(a) Bauxite
(b) Galena
(c) Hematite
(d) Magnetite

Q17. The method of zone refining is based on the principle of:
(a) Volatility
(b) Fractional distillation
(c) Fractional crystallization
(d) Greater solubility of impurities in the melt

Q18. Froth flotation process is used for the concentration of:
(a) Sulphide ores
(b) Oxide ores
(c) Halide ores
(d) None

Q19. Which is the heaviest halogen?
(a) Iodine
(b) Bromine
(c) Astatine
(d) Fluorine

Q20. Which gas is known as laughing gas?
(a) N₂O
(b) NO₂
(c) N₂O₃
(d) NO

Q21. Which of the following is the most electronegative element?
(a) Oxygen
(b) Chlorine
(c) Fluorine
(d) Nitrogen

Q22. Which among the following is a transition element?
(a) Zn
(b) Cu
(c) Ca
(d) Mg

Q23. Potassium dichromate is:
(a) Oxidising agent
(b) Reducing agent
(c) Both
(d) Neutral

Q24. Which ion imparts blue colour to aqueous solutions?
(a) Fe²⁺
(b) Cu²⁺
(c) Mn²⁺
(d) Zn²⁺

Q25. The coordination number of Co in [Co(NH₃)₆]³⁺ is:
(a) 4
(b) 6
(c) 3
(d) 8

Q26. The ligand in [Ni(CO)₄] is:
(a) CO
(b) Ni
(c) Both
(d) None

Q27. Which of the following is an ambidentate ligand?
(a) CN⁻
(b) NH₃
(c) H₂O
(d) CO

Q28. The C–X bond strength is highest in:
(a) C–F
(b) C–Cl
(c) C–Br
(d) C–I

Q29. Which reaction mechanism is followed by tertiary haloalkanes?
(a) SN1
(b) SN2
(c) E1
(d) E2

Q30. Which of the following is used as a refrigerant?
(a) CFCs
(b) Alcohol
(c) Ether
(d) CO₂

Q31. The IUPAC name of CH₃CH₂OH is:
(a) Methanol
(b) Propanol
(c) Ethanol
(d) Butanol

Q32. Phenol on reaction with FeCl₃ gives:
(a) Blue-violet colour
(b) White precipitate
(c) Brown ring
(d) Yellow colour

Q33. Williamson synthesis is used for the preparation of:
(a) Alcohols
(b) Ethers
(c) Phenols
(d) Aldehydes

Q34. Fehling’s test is used to distinguish:

(a) Aldehydes and ketones
(b) Alcohols and phenols
(c) Acids and esters
(d) Amines and amides

Q35. Which reaction converts aldehydes into alcohols?
(a) Reduction
(b) Oxidation
(c) Substitution
(d) Hydrolysis

Q36. The functional group –COOH represents:
(a) Carboxylic acid
(b) Aldehyde
(c) Ketone
(d) Ester

Q37. Aniline reacts with bromine water to give:
(a) 2,4,6-tribromoaniline
(b) Monobromoaniline
(c) p-Bromoaniline
(d) None

Q38. Hinsberg’s test is used to distinguish:
(a) Primary, secondary, and tertiary amines
(b) Aldehydes and ketones
(c) Alcohols and phenols
(d) Acids and esters

Q39. Which of the following is not an amine?
(a) CH₃NH₂
(b) (CH₃)₂NH
(c) C₂H₅OH
(d) (CH₃)₃N

Q40. The building blocks of proteins are:
(a) Nucleotides
(b) Amino acids
(c) Monosaccharides
(d) Fatty acids

Q41. The deficiency of insulin causes:
(a) Diabetes
(b) Tuberculosis
(c) Malaria
(d) Asthma

Q42. Which vitamin is also known as ascorbic acid?
(a) Vitamin A
(b) Vitamin B
(c) Vitamin C
(d) Vitamin D

Q43. Nylon-6 is obtained from:
(a) Caprolactam
(b) Hexamethylenediamine
(c) Adipic acid
(d) Ethylene glycol

Q44. Which of the following is a natural polymer?
(a) Nylon
(b) Bakelite
(c) Rubber
(d) PVC

Q45. The monomer of polystyrene is:
(a) Styrene
(b) Ethylene
(c) Propylene
(d) Vinyl chloride

Q46. Which drug is used as a tranquilizer?
(a) Valium
(b) Ranitidine
(c) Omeprazole
(d) Aspirin

Q47. Aspirin is used as:
(a) Analgesic
(b) Antipyretic
(c) Anti-inflammatory
(d) All of these

Q48. Detergents are sodium salts of:
(a) Fatty acids
(b) Alkyl benzene sulphonic acids
(c) Carboxylic acids
(d) Amines

Q49. Which of the following is an antihistamine?
(a) Chlorpheniramine
(b) Penicillin
(c) Aspirin
(d) Ofloxacin

Q50. Artificial sweetener saccharin is:
(a) 300 times sweeter than sucrose
(b) 500 times sweeter than sucrose
(c) Equal to sucrose
(d) 100 times sweeter than sucrose

Answer Key for CBSE Class 12 Chemistry MCQs (Half Yearly 2026)

Also Check:

CBSE Class 12 Chemistry Half Yearly Sample Paper 2025-26

NCERT Class 12 Chemistry Book 2025-26