C
CraftExam

CBSE Class 10 Science Sample Paper

Marks:
40
Time:
1½ Hours
Questions:
19
Chapters:
11
Session:
2026-27
Class_10_Science_Sample_Paper_CraftExam.pdfA4 · Set A

Academic Session 2026-27

SAMPLE PAPER

SCIENCE

Class X

Time Allowed1½ HoursMaximum Marks40SetA

Assessment: CBSE-Aligned School Assessment

Marks Distribution

SectionQuestion TypeMarks
AMCQs (9×1)9
BShort Answer (4×2)8
CShort Answer (3×3)9
DLong Answer (2×5)10
ECase Study (4×1)4

General Instructions

  1. 1.This question paper has 5 sections.
  2. 2.Marks are shown beside each question.
  3. 3.Read each section instruction carefully.
  4. 4.Attempt only one alternative where internal choice is given.

SECTION A — Objective Type Questions (1×9=9)

Q1 to Q9 are Multiple Choice Questions. Choose the correct option.

Q1. A cloth is to be whitened, and the same chemical is also needed to reduce germs in stored water. Which property makes bleaching powder useful for both jobs?
(1)
  1. (a)It releases chlorine under suitable conditions, so it can bleach and disinfect.
  2. (b)It dissolves into a soapy solution that lifts dirt from fabric.
  3. (c)It is a strong acid that removes stains by neutralising dyes.
  4. (d)It works only by adding extra oxygen to the water.
Q2. A boy and a girl are shown on a pedigree chart. The teacher asks which parent's gamete made the difference in deciding whether the child would be boy or girl. Which answer is correct?
(1)
  1. (a)The mother's egg, because it can carry X or Y.
  2. (b)The father's sperm, because it can carry X or Y.
  3. (c)Both parents equally, because each contributes two sex chromosomes.
  4. (d)Neither parent, because sex is decided only after the baby is born.
Q3. A ductless gland releases a chemical that affects only liver cells and enters the bloodstream first. Which feature makes it a hormone?
(1)
  1. (a)It is carried by blood to a target organ.
  2. (b)It must travel through a nerve fibre to work.
  3. (c)It works only if the gland has a duct.
  4. (d)It is always used as a digestive juice.
Q4. After a classroom cleanup, a teacher asks for two biodegradable items from the list below. Which pair is correct?
(1)
  1. (a)Used notebook pages and a banana peel
  2. (b)Broken chalk and a plastic ruler
  3. (c)Plastic ruler and a banana peel
  4. (d)Used notebook pages and broken chalk
Q5. When magnesium oxide is compared with carbon dioxide, which statement correctly distinguishes the two on the basis of oxide nature?
(1)
  1. (a)Carbon dioxide is acidic, while magnesium oxide is basic
  2. (b)Carbon dioxide is basic, while magnesium oxide is acidic
  3. (c)Both are acidic because both contain oxygen
  4. (d)Both are neutral because both are oxides
Q6. A boy lives in a large multicellular body where many cells are far from the surface. Why can those cells not depend on diffusion alone for oxygen delivery?
(1)
  1. (a)Most body cells are too far from the surface for diffusion to meet the demand quickly
  2. (b)Diffusion can move substances only inside the stomach
  3. (c)Body cells do not need oxygen if blood is present
  4. (d)Diffusion is faster only when blood vessels are absent
Q7. A teacher asks why methane, CH4, is written as a covalent compound instead of an ionic one. Which observation best supports the covalent-bond idea?
(1)
  1. (a)Carbon shares one electron with each hydrogen atom.
  2. (b)Carbon transfers four electrons to four hydrogen atoms.
  3. (c)Carbon accepts one electron from each hydrogen atom.
  4. (d)Carbon forms free electrons that hold the molecule together.
Q8. A student changes only the direction of current in a straight conductor and keeps everything else the same. Which factor actually decides the direction of the magnetic field around the conductor?
(1)
  1. (a)Direction of current
  2. (b)Thickness of the wire
  3. (c)Length of the wire
  4. (d)Colour of the insulation
Q9. A pair of siblings show features from both parents, but they are not exact copies of either parent. What best explains this?
(1)
  1. (a)Fusion of gametes from two parents leads variation
  2. (b)Only one parent contributes all traits
  3. (c)Offspring are always exact copies of the parents
  4. (d)No zygote is formed in this process

SECTION B — Short Answer Questions (2×4=8)

Q10 to Q13 are Short Answer Questions.

Q10. Write one balanced equation each for thermal decomposition, electrolytic decomposition and photochemical decomposition. Also name the energy source in each case.
(2)
Q11. Why should concentrated acid be added to water and not water to concentrated acid?
(2)
Q12. What is meant by feedback mechanism in hormonal coordination? Explain with the example of insulin.
(2)
Q13. Why do our leg muscles often cramp after we run very fast for a long time?
(2)

SECTION C — Short Answer Questions (3×3=9)

Q14 to Q16 are Short Answer Questions.

Q14. A teacher performs four demonstrations in class: burning magnesium ribbon, adding water to calcium oxide, heating ferrous sulphate crystals, and dipping an iron nail in copper sulphate solution. Explain what each demonstration is meant to teach about chemical reactions.
(3)
Q15. Why does soap not work well in hard water? What is scum, and how is it formed?
(3)
Q16. What is the thermit reaction? Why is aluminium used in this reaction? Mention one practical application.
(3)

SECTION D — Long Answer Questions (5×2=10)

Q17 to Q18 are Long Answer Questions.

Q17. Why is the Sun visible about two minutes before actual sunrise and about two minutes after actual sunset? Also explain the apparent flattening of the Sun near the horizon.
(5)
Q18. Describe the processes of corrosion and rancidity. How are they similar in terms of chemistry? Describe three practical ways to prevent each. Why is preventing these processes economically important?
(5)

OR

Q18. Describe the role of adrenaline in preparing the body for an emergency situation.
(5)

SECTION E — Case-Based Questions (1×4=4)

Q19 is a case-based question. Read the case carefully and answer the sub-questions.

Q19

A child is stung by a bee while playing in a garden. Later, during a walk, another person accidentally touches nettle leaves and feels a burning pain. In both cases, a mild base is suggested as a remedy.
(i) Why does a bee sting cause pain and irritation?
(1)
(ii) Why can baking soda give relief from a bee sting?
(1)
(iii) What acid is injected by nettle leaves?
(1)
(iv) What principle is common to the remedies for both stings?
(1)

End of Question Paper