Class 10 · Science · CBSE Board · 2023–2026

Chemical Reactions and Equations — Class 10 Science PYQs

37 questions from this chapter, asked in 4 Class 10 exams between 2023–2026 — every question paper set included, duplicates removed.

37questions

4Class 10 exams

2023–2026years covered

1 / 2 / 3mark values asked

Questions asked per year

20263 Qs 20259 Qs 202413 Qs 202312 Qs

Practice questions

Q1MCQ20261 mark

Answer Logic

(i) $AgN O_{3} + NaCl \to NaN O_{3} + AgCl$
(ii) $K_{2} S O_{4} + BaC l_{2} \to BaS O_{4} + 2KCl$
Which of the following options clearly describes both the reactions ?

(A)(i) is double displacement, (ii) is displacement reaction.

(B)Both, (i) and (ii) are displacement reactions and precipitation reactions.

(C)Both, (i) and (ii) are double displacement reactions and precipitation reactions.

(D)(i) is displacement, (ii) is double displacement reaction.

Q2MCQ20261 mark

Answer Logic

The gases evolved on heating lead (II) nitrate crystals are :

(A)

NO

and

O_{2}

(B)

N_{2}

and

N O_{2}

(C)

N O_{2}

and

H_{2}

(D)

N O_{2}

and

O_{2}

Q320263 marks

Answer Logic

(a) Name the substance oxidised and reduced in the following reaction :
$ZnO + C \to Zn + CO$
(b) Balance the following chemical reaction :
$Pb (N O_{3})_{2} + KI \to Pb I_{2} + KN O_{3}$
(c) Give one example each of electrolytic decomposition and decomposition by sunlight.

Q4MCQ20251 mark

Answer Logic

Electrolysis of water is a decomposition reaction. The mass ratio
( $M_{H} : M_{O}$ ) of hydrogen and oxygen gases liberated at the electrodes
during electrolysis of water is :

(A)8 : 1

(B)2 : 1

(C)1 : 2

(D)1 : 8

Q520251 mark

Answer Logic

Assertion (A) : Decomposition reactions are generally endothermic reactions.
Reason (R) : Decomposition of organic matter into compost is an exothermic process.

Q620252 marks

Answer Logic

A student performs the following experiment in his school laboratory.
List two observations to justify that in this experiment a chemical change has taken place.

Q720252 marks

Answer Logic

What happens when : (write balanced chemical equation)
(a) Lead nitrate is thermally decomposed,
(b) Natural gas burns in oxygen (or air) ?

Q820252 marks

Answer Logic

Translate the following statements into chemical equations and then balance them :
(a) Nitric acid reacts with calcium hydroxide to form calcium nitrate and water.
(b) Sodium chloride reacts with silver nitrate to form silver chloride and sodium nitrate.

Q9MCQ20251 mark

Answer Logic

The correct balanced chemical equation showing exothermic reaction in which natural gas burns in air is :

(A)

C H_{4} + O_{2} ⟶ C O_{2} + 2 H_{2} O

(B)

C H_{4} + 2 O_{2} ⟶ 2C O_{2} + 2 H_{2} O + Energy

(C)

C H_{4} + 2 O_{2} ⟶ C O_{2} + 2 H_{2} O

(D)

C H_{4} + 2 O_{2} ⟶ C O_{2} + 2 H_{2} O + Energy

Q1020252 marks

Answer Logic

Balance the following chemical equations :
(a) $C O_{2} + H_{2} O Sunlight/Chlorophyll C_{6} H_{12} O_{6} + O_{2} + H_{2} O$
(b) $Pb (N O_{3})_{2} Heat PbO + N O_{2} + O_{2}$

Why practise Chemical Reactions and Equations PYQs?

Chemical Reactions and Equations has appeared in 4 Class 10 Science exams we track between 2023–2026, with questions worth 1, 2, 3 marks. CBSE Board examiners consistently reuse concepts and question patterns from this topic — practising its previous year questions is the most reliable way to know exactly what to expect in your exam.

Chemical Reactions and Equations — Class 10 Science PYQs

Questions asked per year

Practice questions

Why practise Chemical Reactions and Equations PYQs?

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