CN  ChemNexa

Chemical Reactions and Equations CBSE Class 10 MCQ & Practice Questions

Practice Chemical Reactions and Equations MCQs for CBSE Class 10 Chemistry with answers, explanations, chapter revision and related ChemNexa mock tests.

Register Free for Full Chemistry Practice

Chemical Reactions and Equations Revision Guide for CBSE Class 10 Chemistry

Chemical Reactions and Equations is part of CBSE Class 10 Chemistry preparation. A strong revision plan should combine concept review with exam-style questions so that definitions, relationships, calculations and exceptions are recalled accurately.

Use the sample MCQs on this page to check understanding, then attempt the related ChemNexa tests for broader practice. When an answer is wrong, review the explanation and return to the underlying concept before attempting another set.

Important Topics

  • Core definitions and principles
  • Important equations or relationships
  • Common applications and examples
  • Frequently confused concepts
  • Exam-style multiple-choice questions
  • Error review and targeted revision

Revision Tip

Create a one-page summary of trends, structures, reactions, exceptions and key terminology for Chemical Reactions and Equations, then test recall with mixed MCQs.

What to practise in Chemical Reactions and Equations

Concept Revision

Revise definitions, principles, equations, trends and core ideas from Chemical Reactions and Equations before attempting MCQs.

Exam-style MCQs

Use chapter-focused multiple-choice practice to improve accuracy, recall and application for CBSE Class 10 Chemistry.

Performance Practice

Attempt ChemNexa tests, review results and return to weak areas for another round of targeted revision.

Top 20 Chemical Reactions and Equations MCQs with Answers

These public questions are selected from the exact Chemical Reactions and Equations chapter, screened for topic relevance and deduplicated so repeated versions of the same MCQ are not shown publicly. Use them for quick revision, then sign in to attempt the complete test experience with more questions, results and performance review.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

1. Which set of coefficients correctly balances Fe + H₂O → Fe₃O₄ + H₂?

  • A. 3, 4, 1, 4
  • B. 4, 3, 1, 4
  • C. 3, 2, 1, 3
  • D. 2, 4, 1, 3
Answer: A
Explanation: The balanced equation is 3Fe + 4H₂O → Fe₃O₄ + 4H₂.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

2. In the reaction 2Mg + O₂ → 2MgO, magnesium undergoes

  • A. Reduction only
  • B. Neutralisation
  • C. Oxidation
  • D. Displacement without oxidation
Answer: C
Explanation: Magnesium combines with oxygen and loses electrons, so it is oxidised.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

3. Which reaction is a combination reaction?

  • A. CaCO₃ → CaO + CO₂
  • B. Zn + CuSO₄ → ZnSO₄ + Cu
  • C. CaO + H₂O → Ca(OH)₂
  • D. AgNO₃ + NaCl → AgCl + NaNO₃
Answer: C
Explanation: Two reactants combine to form a single product.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

4. Which reaction is a thermal decomposition reaction?

  • A. 2H₂ + O₂ → 2H₂O
  • B. CaCO₃ → CaO + CO₂
  • C. Fe + CuSO₄ → FeSO₄ + Cu
  • D. HCl + NaOH → NaCl + H₂O
Answer: B
Explanation: Calcium carbonate decomposes on heating into calcium oxide and carbon dioxide.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

5. A white precipitate is formed when aqueous AgNO₃ reacts with aqueous NaCl. The precipitate is

  • A. NaNO₃
  • B. Ag
  • C. AgCl
  • D. Cl₂
Answer: C
Explanation: Ag⁺ and Cl⁻ ions combine to form insoluble AgCl.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

6. Which observation confirms that a chemical reaction has occurred when zinc reacts with dilute HCl?

  • A. Only cooling
  • B. No visible change
  • C. Evolution of hydrogen gas
  • D. Formation of a blue precipitate
Answer: C
Explanation: Hydrogen gas is evolved: Zn + 2HCl → ZnCl₂ + H₂.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

7. Which reaction is a displacement reaction?

  • A. 2KClO₃ → 2KCl + 3O₂
  • B. Na₂SO₄ + BaCl₂ → BaSO₄ + 2NaCl
  • C. Zn + CuSO₄ → ZnSO₄ + Cu
  • D. CaO + H₂O → Ca(OH)₂
Answer: C
Explanation: Zinc displaces copper from copper sulphate.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

8. Which reaction is a double displacement reaction?

  • A. C + O₂ → CO₂
  • B. Fe + S → FeS
  • C. BaCl₂ + Na₂SO₄ → BaSO₄ + 2NaCl
  • D. 2HgO → 2Hg + O₂
Answer: C
Explanation: Ions exchange partners to form BaSO₄ and NaCl.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

9. The brown coating formed on iron in moist air is mainly

  • A. FeO
  • B. Fe₃O₄ only
  • C. Hydrated iron(III) oxide
  • D. Iron sulphide
Answer: C
Explanation: Rust is mainly hydrated ferric oxide, Fe₂O₃·xH₂O.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

10. Rancidity in oily food is mainly caused by

  • A. Reduction
  • B. Oxidation
  • C. Neutralisation
  • D. Hydrolysis only
Answer: B
Explanation: Oils and fats undergo oxidation, producing unpleasant smell and taste.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

11. Which method helps prevent rancidity most effectively?

  • A. Keeping food exposed to air
  • B. Adding water
  • C. Using antioxidants and airtight packing
  • D. Heating continuously
Answer: C
Explanation: Antioxidants and reduced oxygen exposure slow oxidation.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

12. In CuO + H₂ → Cu + H₂O, the substance reduced is

  • A. H₂
  • B. H₂O
  • C. CuO
  • D. Cu
Answer: C
Explanation: CuO loses oxygen and is reduced to Cu.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

13. In CuO + H₂ → Cu + H₂O, hydrogen acts as

  • A. Oxidising agent
  • B. Catalyst
  • C. Reducing agent
  • D. Precipitating agent
Answer: C
Explanation: Hydrogen removes oxygen from CuO and is itself oxidised to water.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

14. Which equation represents an exothermic reaction?

  • A. CaCO₃ → CaO + CO₂
  • B. 2AgCl → 2Ag + Cl₂
  • C. CH₄ + 2O₂ → CO₂ + 2H₂O + heat
  • D. 2H₂O → 2H₂ + O₂
Answer: C
Explanation: Combustion of methane releases heat.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

15. Which equation represents a photochemical decomposition reaction?

  • A. 2AgCl → 2Ag + Cl₂ in sunlight
  • B. CaO + H₂O → Ca(OH)₂
  • C. Fe + CuSO₄ → FeSO₄ + Cu
  • D. NaOH + HCl → NaCl + H₂O
Answer: A
Explanation: Silver chloride decomposes in sunlight.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

16. What is the colour change when iron nails are dipped in copper sulphate solution?

  • A. Colourless to pink
  • B. Blue solution becomes greenish
  • C. Green solution becomes blue
  • D. No change
Answer: B
Explanation: Fe displaces Cu, forming pale green FeSO₄ and copper deposit.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

17. Which gas is evolved when lead nitrate is heated?

  • A. Only H₂
  • B. Only O₂
  • C. NO₂ and O₂
  • D. CO₂ only
Answer: C
Explanation: 2Pb(NO₃)₂ → 2PbO + 4NO₂ + O₂.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

18. The yellow residue formed on heating lead nitrate is

  • A. Pb
  • B. PbO₂
  • C. PbO
  • D. PbCl₂
Answer: C
Explanation: Lead nitrate decomposes to yellow lead(II) oxide.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

19. Which statement about a balanced chemical equation is correct?

  • A. It has equal number of molecules on both sides
  • B. It always has equal masses of each compound
  • C. It has equal number of atoms of each element on both sides
  • D. It must contain a catalyst
Answer: C
Explanation: Balancing ensures conservation of atoms and therefore mass.

CBSE Class 10 Chemistry · Chemical Reactions and Equations · Very Very Hard

20. Why is magnesium ribbon cleaned before burning?

  • A. To cool it
  • B. To remove MgO coating
  • C. To add oxygen
  • D. To reduce its mass
Answer: B
Explanation: The oxide layer prevents magnesium from burning readily.

Login to Start Full Test

Chemical Reactions and Equations Practice Tests

Chemical Reactions and Equations Frequently Asked Questions

How should I prepare Chemical Reactions and Equations for CBSE Class 10 Chemistry?

Revise the core concepts first, make a short list of important relationships or exceptions, and then solve chapter-focused MCQs while reviewing every error.

How can ChemNexa help with Chemical Reactions and Equations practice?

This page provides public sample questions and links to published ChemNexa tests so you can combine quick revision with structured practice.

What should I do after getting an MCQ wrong?

Identify whether the mistake came from a concept gap, calculation, unit, sign, wording or memory error, review that point, and then attempt a similar question again.

Continue with another chapter to build connected concepts and strengthen your overall Chemistry preparation.

Continue CBSE Class 10 Chemistry

View all CBSE Class 10 chapters and testsBrowse all Chemistry PracticeCreate a free account