Class 10 Science Chemical Reactions and Equations Sample Paper Style Practice
Sample Paper Style Practice for Class 10 Science Chemical Reactions and Equations. Try first, then reveal the answer. These are exam-oriented practice items, not copied board papers.
Practice questions aligned to NCERT topics used in CBSE classrooms. These are original exam-oriented questions for revision — not official CBSE board papers and not a guarantee of any exam question. Always match the textbook issued by your school and the latest PDFs on ncert.nic.in and cbseacademic.nic.in.
Answers opened: 0
Practice set
Q1MCQ1 markEasyRevision pick
Choose the correct statement related to Balanced equation in the chapter Chemical Reactions and Equations.
A. An exothermic reaction releases heat to the surroundings
B. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
C. Mass need not be conserved
D. A balanced chemical equation has the same number of atoms of each element on both sides
Answer
D. A balanced chemical equation has the same number of atoms of each element on both sides
Explanation
A balanced chemical equation has the same number of atoms of each element on both sides. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q2MCQ1 markEasy
Choose the correct statement related to Combination reaction in the chapter Chemical Reactions and Equations.
A. In a combination reaction two or more substances join to form a single product
B. A more reactive metal can displace a less reactive metal from its salt solution
C. An endothermic reaction absorbs heat from the surroundings
D. Combination, decomposition, displacement, double displacement
Answer
A. In a combination reaction two or more substances join to form a single product
Explanation
In a combination reaction two or more substances join to form a single product. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q3MCQ1 markEasy
Choose the correct statement related to Decomposition in the chapter Chemical Reactions and Equations.
A. A precipitate is an insoluble solid formed in a double-displacement reaction
B. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
C. Oxidation and reduction occur together in a redox reaction
D. Redox: oxidation is gain of oxygen or loss of electrons as taught
Answer
B. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
Explanation
A decomposition reaction splits one compound into two or more products, often with heat, light or electricity. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q4MCQ1 markEasy
Choose the correct statement related to Displacement in the chapter Chemical Reactions and Equations.
A. A more reactive metal can displace a less reactive metal from its salt solution
B. An exothermic reaction releases heat to the surroundings
C. Exothermic vs endothermic
D. A chemical equation must be balanced for mass
Answer
A. A more reactive metal can displace a less reactive metal from its salt solution
Explanation
A more reactive metal can displace a less reactive metal from its salt solution. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q5MCQ1 markModerateRevision pick
Choose the correct statement related to Redox in the chapter Chemical Reactions and Equations.
A. Combination, decomposition, displacement, double displacement
B. Precipitation reactions
C. Oxidation and reduction occur together in a redox reaction
D. An endothermic reaction absorbs heat from the surroundings
Answer
C. Oxidation and reduction occur together in a redox reaction
Explanation
Oxidation and reduction occur together in a redox reaction. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q6MCQ1 markEasy
Choose the correct statement related to Exothermic in the chapter Chemical Reactions and Equations.
A. Redox: oxidation is gain of oxygen or loss of electrons as taught
B. A precipitate is an insoluble solid formed in a double-displacement reaction
C. This idea is not part of the NCERT chapter
D. An exothermic reaction releases heat to the surroundings
Answer
D. An exothermic reaction releases heat to the surroundings
Explanation
An exothermic reaction releases heat to the surroundings. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q7MCQ1 markEasy
Choose the correct statement related to Endothermic in the chapter Chemical Reactions and Equations.
A. An endothermic reaction absorbs heat from the surroundings
B. The textbook says the opposite of this statement
C. A chemical equation must be balanced for mass
D. Exothermic vs endothermic
Answer
A. An endothermic reaction absorbs heat from the surroundings
Explanation
An endothermic reaction absorbs heat from the surroundings. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q8MCQ1 markEasy
Choose the correct statement related to Precipitation in the chapter Chemical Reactions and Equations.
A. Precipitation reactions
B. This happens only in a laboratory and never in daily life
C. A precipitate is an insoluble solid formed in a double-displacement reaction
D. Combination, decomposition, displacement, double displacement
Answer
C. A precipitate is an insoluble solid formed in a double-displacement reaction
Explanation
A precipitate is an insoluble solid formed in a double-displacement reaction. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q9MCQ1 markEasyRevision pick
Choose the correct statement related to Chemical Reactions and Equations in the chapter Chemical Reactions and Equations.
A. A chemical equation must be balanced for mass
B. A balanced chemical equation has the same number of atoms of each element on both sides
C. Redox: oxidation is gain of oxygen or loss of electrons as taught
D. This idea is not part of the NCERT chapter
Answer
A. A chemical equation must be balanced for mass
Explanation
A chemical equation must be balanced for mass. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q10MCQ1 markModerate
Choose the correct statement related to Chemical Reactions and Equations in the chapter Chemical Reactions and Equations.
A. The textbook says the opposite of this statement
B. Combination, decomposition, displacement, double displacement
C. In a combination reaction two or more substances join to form a single product
D. Exothermic vs endothermic
Answer
B. Combination, decomposition, displacement, double displacement
Explanation
Combination, decomposition, displacement, double displacement. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q11MCQ1 markEasy
Choose the correct statement related to Redox in the chapter Chemical Reactions and Equations.
A. Precipitation reactions
B. Redox: oxidation is gain of oxygen or loss of electrons as taught
C. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
D. This happens only in a laboratory and never in daily life
Answer
B. Redox: oxidation is gain of oxygen or loss of electrons as taught
Explanation
Redox: oxidation is gain of oxygen or loss of electrons as taught. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q12MCQ1 markEasy
Choose the correct statement related to Chemical Reactions and Equations in the chapter Chemical Reactions and Equations.
A. A more reactive metal can displace a less reactive metal from its salt solution
B. This idea is not part of the NCERT chapter
C. A balanced chemical equation has the same number of atoms of each element on both sides
D. Exothermic vs endothermic
Answer
D. Exothermic vs endothermic
Explanation
Exothermic vs endothermic. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q13MCQ1 markEasyRevision pick
Choose the correct statement related to Chemical Reactions and Equations in the chapter Chemical Reactions and Equations.
A. In a combination reaction two or more substances join to form a single product
B. The textbook says the opposite of this statement
C. Oxidation and reduction occur together in a redox reaction
D. Precipitation reactions
Answer
D. Precipitation reactions
Explanation
Precipitation reactions. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q14MCQ1 markEasy
Choose the correct statement related to Balanced equation in the chapter Chemical Reactions and Equations.
A. Precipitation reactions
B. This happens only in a laboratory and never in daily life
C. A balanced chemical equation has the same number of atoms of each element on both sides
D. A skeleton equation is already balanced
Answer
C. A balanced chemical equation has the same number of atoms of each element on both sides
Explanation
A balanced chemical equation has the same number of atoms of each element on both sides. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q15MCQ1 markModerate
Choose the correct statement related to Combination reaction in the chapter Chemical Reactions and Equations.
A. A precipitate is an insoluble solid formed in a double-displacement reaction
B. Oxidation and reduction occur together in a redox reaction
C. In a combination reaction two or more substances join to form a single product
D. A balanced chemical equation has the same number of atoms of each element on both sides
Answer
C. In a combination reaction two or more substances join to form a single product
Explanation
In a combination reaction two or more substances join to form a single product. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q16MCQ1 markEasy
Choose the correct statement related to Decomposition in the chapter Chemical Reactions and Equations.
A. In a combination reaction two or more substances join to form a single product
B. An exothermic reaction releases heat to the surroundings
C. A chemical equation must be balanced for mass
D. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
Answer
D. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
Explanation
A decomposition reaction splits one compound into two or more products, often with heat, light or electricity. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q17MCQ1 markEasyRevision pick
Choose the correct statement related to Displacement in the chapter Chemical Reactions and Equations.
A. A decomposition reaction splits one compound into two or more products, often with heat, light or electricity
B. A more reactive metal can displace a less reactive metal from its salt solution
C. Combination, decomposition, displacement, double displacement
D. An endothermic reaction absorbs heat from the surroundings
Answer
B. A more reactive metal can displace a less reactive metal from its salt solution
Explanation
A more reactive metal can displace a less reactive metal from its salt solution. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q18MCQ1 markEasy
Choose the correct statement related to Redox in the chapter Chemical Reactions and Equations.
A. A precipitate is an insoluble solid formed in a double-displacement reaction
B. Redox: oxidation is gain of oxygen or loss of electrons as taught
C. Oxidation and reduction occur together in a redox reaction
D. A more reactive metal can displace a less reactive metal from its salt solution
Answer
C. Oxidation and reduction occur together in a redox reaction
Explanation
Oxidation and reduction occur together in a redox reaction. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q19MCQ1 markEasy
Choose the correct statement related to Exothermic in the chapter Chemical Reactions and Equations.
A. Oxidation and reduction occur together in a redox reaction
B. A chemical equation must be balanced for mass
C. Exothermic vs endothermic
D. An exothermic reaction releases heat to the surroundings
Answer
D. An exothermic reaction releases heat to the surroundings
Explanation
An exothermic reaction releases heat to the surroundings. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q20MCQ1 markModerate
Choose the correct statement related to Endothermic in the chapter Chemical Reactions and Equations.
A. An endothermic reaction absorbs heat from the surroundings
B. Precipitation reactions
C. An exothermic reaction releases heat to the surroundings
D. Combination, decomposition, displacement, double displacement
Answer
A. An endothermic reaction absorbs heat from the surroundings
Explanation
An endothermic reaction absorbs heat from the surroundings. The other options mix ideas from nearby topics or reverse the textbook fact.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q413 Mark3 marksModerateRevision pick
Explain Combination reaction in about three points, with one example.
Answer
In a combination reaction two or more substances join to form a single product. Example: CaO + H2O → Ca(OH)2
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q423 Mark3 marksModerate
Explain Decomposition in about three points, with one example.
Answer
A decomposition reaction splits one compound into two or more products, often with heat, light or electricity. Example: Use a situation from the NCERT activity or a labelled diagram in this chapter.
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q433 Mark3 marksModerate
Explain Displacement in about three points, with one example.
Answer
A more reactive metal can displace a less reactive metal from its salt solution. Example: Use a situation from the NCERT activity or a labelled diagram in this chapter.
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q443 Mark3 marksDifficult
Explain Redox in about three points, with one example.
Answer
Oxidation and reduction occur together in a redox reaction. Example: Use a situation from the NCERT activity or a labelled diagram in this chapter.
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q453 Mark3 marksModerateRevision pick
Explain Exothermic in about three points, with one example.
Answer
An exothermic reaction releases heat to the surroundings. Example: Respiration and many combustions
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q463 Mark3 marksModerate
Explain Endothermic in about three points, with one example.
Answer
An endothermic reaction absorbs heat from the surroundings. Example: Photosynthesis
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q473 Mark3 marksModerate
Explain Precipitation in about three points, with one example.
Answer
A precipitate is an insoluble solid formed in a double-displacement reaction. Example: Use a situation from the NCERT activity or a labelled diagram in this chapter.
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q483 Mark3 marksDifficult
Explain Chemical Reactions and Equations in about three points, with one example.
Answer
A chemical equation must be balanced for mass. Example: Use a situation from the NCERT activity or a labelled diagram in this chapter.
Explanation
Three-mark questions want a short explanation, not a full essay. Link the idea to a figure or an activity.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q555 Mark5 marksModerate
Write a long answer on Decomposition. Include definition, explanation and one application.
Answer
Decomposition — A decomposition reaction splits one compound into two or more products, often with heat, light or electricity. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q565 Mark5 marksModerate
Write a long answer on Displacement. Include definition, explanation and one application.
Answer
Displacement — A more reactive metal can displace a less reactive metal from its salt solution. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q575 Mark5 marksDifficultRevision pick
Write a long answer on Redox. Include definition, explanation and one application.
Answer
Redox — Oxidation and reduction occur together in a redox reaction. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q585 Mark5 marksModerate
Write a long answer on Exothermic. Include definition, explanation and one application.
Answer
Exothermic — An exothermic reaction releases heat to the surroundings. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q595 Mark5 marksModerate
Write a long answer on Endothermic. Include definition, explanation and one application.
Answer
Endothermic — An endothermic reaction absorbs heat from the surroundings. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q605 Mark5 marksDifficult
Write a long answer on Precipitation. Include definition, explanation and one application.
Answer
Precipitation — A precipitate is an insoluble solid formed in a double-displacement reaction. Explain the idea in order (definition → working → result). End with one application from daily life or a numerical/diagram if the chapter has one.
Explanation
Long answers are marked for structure. Use headings or numbered steps so the examiner can see each part.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q61Assertion and Reason1 markModerate
Assertion (A): A chemical equation must be balanced for mass.
Reason (R): Chemical Reactions and Equations is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q62Assertion and Reason1 markModerate
Assertion (A): Combination, decomposition, displacement, double displacement.
Reason (R): Chemical Reactions and Equations is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q63Assertion and Reason1 markModerate
Assertion (A): Redox: oxidation is gain of oxygen or loss of electrons as taught.
Reason (R): Redox is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q64Assertion and Reason1 markDifficult
Assertion (A): Exothermic vs endothermic.
Reason (R): Chemical Reactions and Equations is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q65Assertion and Reason1 markModerate
Assertion (A): Precipitation reactions.
Reason (R): Chemical Reactions and Equations is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q66Assertion and Reason1 markModerate
Assertion (A): A balanced chemical equation has the same number of atoms of each element on both sides.
Reason (R): Balanced equation is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q67Assertion and Reason1 markModerate
Assertion (A): In a combination reaction two or more substances join to form a single product.
Reason (R): Combination reaction is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q68Assertion and Reason1 markDifficult
Assertion (A): A decomposition reaction splits one compound into two or more products, often with heat, light or electricity.
Reason (R): Decomposition is a key idea in the chapter Chemical Reactions and Equations.
Choose the correct option.
A. Both A and R are true, and R is the correct explanation of A.
B. Both A and R are true, and R is not the correct explanation of A.
C. A is true but R is false.
D. A is false but R is true.
Answer
A. Both A and R are true, and R is the correct explanation of A.
Explanation
Read Assertion and Reason separately first. Here both match the textbook idea, and R explains why A is taught in this chapter.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q69Case Based4 marksModerateRevision pick
A student is revising Chemical Reactions and Equations and notes: “A more reactive metal can displace a less reactive metal from its salt solution.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Displacement.
(ii) A more reactive metal can displace a less reactive metal from its salt solution.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q70Case Based4 marksModerate
A student is revising Chemical Reactions and Equations and notes: “Oxidation and reduction occur together in a redox reaction.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Redox.
(ii) Oxidation and reduction occur together in a redox reaction.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q71Case Based4 marksModerate
A student is revising Chemical Reactions and Equations and notes: “An exothermic reaction releases heat to the surroundings.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Exothermic.
(ii) An exothermic reaction releases heat to the surroundings.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q72Case Based4 marksDifficult
A student is revising Chemical Reactions and Equations and notes: “An endothermic reaction absorbs heat from the surroundings.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Endothermic.
(ii) An endothermic reaction absorbs heat from the surroundings.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q73Case Based4 marksModerateRevision pick
A student is revising Chemical Reactions and Equations and notes: “A precipitate is an insoluble solid formed in a double-displacement reaction.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Precipitation.
(ii) A precipitate is an insoluble solid formed in a double-displacement reaction.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q74Case Based4 marksModerate
A student is revising Chemical Reactions and Equations and notes: “A chemical equation must be balanced for mass.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Chemical Reactions and Equations.
(ii) A chemical equation must be balanced for mass.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q75Case Based4 marksModerate
A student is revising Chemical Reactions and Equations and notes: “Combination, decomposition, displacement, double displacement.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Chemical Reactions and Equations.
(ii) Combination, decomposition, displacement, double displacement.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q76Case Based4 marksDifficult
A student is revising Chemical Reactions and Equations and notes: “Redox: oxidation is gain of oxygen or loss of electrons as taught.” Using this case, answer: (i) Name the idea. (ii) State it in your own words. (iii) Give one classroom or daily-life use.
Answer
(i) Redox.
(ii) Redox: oxidation is gain of oxygen or loss of electrons as taught.
(iii) Apply it in a school experiment, a labelled diagram, or a situation described in the NCERT chapter.
Explanation
Case-based items recycle a short story. Pull the fact out first, then apply it. This is original practice in CBSE case style — not a copied board paper.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q77Competency Based3 marksModerateRevision pick
Competency practice: A classmate can recall the heading Chemical Reactions and Equations but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — Exothermic vs endothermic. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q78Competency Based3 marksDifficult
Competency practice: A classmate can recall the heading Chemical Reactions and Equations but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — Precipitation reactions. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q79Competency Based3 marksModerate
Competency practice: A classmate can recall the heading Balanced equation but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — A balanced chemical equation has the same number of atoms of each element on both sides. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q80Competency Based3 marksModerate
Competency practice: A classmate can recall the heading Combination reaction but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — In a combination reaction two or more substances join to form a single product. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q81Competency Based3 marksDifficultRevision pick
Competency practice: A classmate can recall the heading Decomposition but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — A decomposition reaction splits one compound into two or more products, often with heat, light or electricity. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q82Competency Based3 marksModerate
Competency practice: A classmate can recall the heading Displacement but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — A more reactive metal can displace a less reactive metal from its salt solution. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q83Competency Based3 marksModerate
Competency practice: A classmate can recall the heading Redox but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — Oxidation and reduction occur together in a redox reaction. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
Q84Competency Based3 marksDifficult
Competency practice: A classmate can recall the heading Exothermic but cannot explain it. How will you teach it in two steps using the textbook idea?
Answer
Step 1: State the fact — An exothermic reaction releases heat to the surroundings. Step 2: Show one example or diagram from the chapter and ask the classmate to repeat it in their own words.
Explanation
Competency-based items check whether you can use a concept, not only name it. Teach-back is a simple way to prove understanding.
Meta
Class: Class 10 · Subject: Science · Chapter: Chemical Reactions and Equations · Original GKSchools practice (NCERT-aligned, not an official CBSE paper).
FAQs
Are these official CBSE board questions?
No. They are original practice questions aligned to NCERT topics used in CBSE classrooms. Official sample papers are published on cbseacademic.nic.in.
Will these questions appear in the board exam?
Nobody can promise a question. Use them for revision of frequently tested concepts and exam-style practice.
Is the chapter list the latest NCERT list?
Yes, the catalog follows current NCERT textbooks used in CBSE schools (including new middle-stage books such as Ganita Prakash and Curiosity). Always match the book issued by your school.
How should I use the 100 questions?
Try the question first, then tap Show answer. Mix MCQs with long answers. Revise formulas and diagrams from the textbook alongside this set.
Where are NCERT solutions?
Open the NCERT-style practice link on this subject or chapter. For word-for-word textbook exercise answers, use the NCERT book itself; we do not copy solution keys from other websites.
What is the suggested URL pattern?
Hub /cbse/, then /cbse/class-10/, then subject and chapter slugs.
Why is this a separate URL?
So students searching for “Sample Paper Style Practice” land on a filtered set, while the chapter page remains the full 100-question bank. Same facts, different search intent.
Today's 3-step path
Follow this loop every day: mixed test, current affairs, then today's subject. A new set arrives tomorrow.
