Class 10 Science — Chapter 1: Chemical Reactions and Equations
68 practice questions · 23 Easy · 23 Medium · 22 Hard
Practise Class 10 Science Chapter 1, "Chemical Reactions and Equations", with 68 NCERT-aligned multiple-choice questions. The set is split into 23 Easy, 23 Medium and 22 Hard questions, so you can warm up on the fundamentals and then push into the exam-level problems that separate top scorers in CBSE Board exams and the JEE & NEET foundation years.
"Chemical Reactions and Equations" is one of the chapters where concept clarity across physics, chemistry and biology basics really pays off. Each MCQ on this chapter is timed and uses exam-grade marking (+2 correct, −1 wrong, 0 skipped), training the same accuracy-under-pressure that real papers demand. Every question carries a short explanation, so a wrong answer becomes a quick lesson rather than a dead end — the fastest way to close gaps before a test.
Use this chapter as targeted revision: attempt the Easy set first to confirm your basics on Chemical Reactions and Equations, then move to Medium and Hard to test application and problem-solving. Your accuracy, streaks and XP save automatically, and the chapter feeds into your overall Class 10 Science mastery score. A few sample questions are shown below; sign in free to practise all 68.
Key concepts: Chemical Reactions and Equations (Class 10 Science)
Chemical changes are written as balanced equations. This chapter classifies reactions and explains everyday effects like corrosion and rancidity.
- Balanced chemical equation
- Reactants → products, with equal atoms of each element on both sides (law of conservation of mass). Add state symbols (s, l, g, aq).
- Combination & decomposition
- Combination: two or more substances form one product. Decomposition: one compound breaks into simpler ones (by heat, light or electricity).
- Displacement & double displacement
- A more reactive element displaces a less reactive one; double displacement is an exchange of ions (precipitation, neutralisation).
- Oxidation & reduction (redox)
- Oxidation = gain of oxygen / loss of hydrogen; reduction is the reverse. They always occur together.
- Exothermic vs endothermic
- Exothermic reactions release heat (respiration, combustion); endothermic reactions absorb heat.
- Corrosion & rancidity
- Slow oxidation of metals (rusting) and of fats/oils in food (rancidity); prevented by painting, galvanising or flushing with nitrogen.
Key formulas — Chemical Reactions and Equations
💡 Exam tips for Chemical Reactions and Equations
- Balance metals first, then non-metals, then hydrogen and oxygen last.
- Formation of a precipitate or a gas is a clue that a double-displacement reaction has occurred.
Sample questions
Oxidation involves:
Oxidation = gain of O / loss of H (or loss of electrons in modern terms).
Balance: Fe + H₂O → Fe₃O₄ + H₂. The coefficients (in order) are:
3Fe + 4H₂O → Fe₃O₄ + 4H₂. Check: 3 Fe, 8 H, 4 O on each side.
In the reaction CuO + H₂ → Cu + H₂O, the substance reduced is:
CuO loses oxygen → reduction. H₂ gains oxygen → oxidation.
Chemical Reactions and Equations — FAQs
What are the key concepts in Class 10 Science Chemical Reactions and Equations?+
Chemical changes are written as balanced equations. This chapter classifies reactions and explains everyday effects like corrosion and rancidity. Key ideas include Balanced chemical equation, Combination & decomposition, Displacement & double displacement, Oxidation & reduction (redox), Exothermic vs endothermic.
What does Class 10 Science Chapter 1 (Chemical Reactions and Equations) cover on XamBaaz?+
It covers 68 NCERT-aligned MCQs on "Chemical Reactions and Equations" — 23 Easy, 23 Medium and 22 Hard — each with a timed quiz and an instant explanation, suitable for CBSE Board exams and the JEE & NEET foundation years.
Are these "Chemical Reactions and Equations" questions free to practise?+
Yes — sign in with Google to practise "Chemical Reactions and Equations" free. Full unlimited access is ₹999/year (limited-time launch price), with no per-chapter charges.
How should I revise "Chemical Reactions and Equations" for the exam?+
Start with the Easy quiz to confirm your fundamentals, then attempt Medium and Hard for application-level practice. Review each explanation, retry the questions you miss, and track your accuracy on this chapter until it is consistently high.
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