CREST Science Olympiad Class 10 Previous Year Paper

Getting ready for the Class 10 Science Olympiad? Practising with previous year question papers is one of the smartest ways to prepare. These papers help students understand the level of questions asked and focus on the most important concepts during revision.

Why These Papers Are a Must-Have

• They include questions from vital topics like Chemical Reactions and Equations, Acids, Bases and Salts, Metals and Non-metals etc.
• They help improve speed, accuracy, and confidence when solving science problems under exam conditions.
• Each paper comes with an answer key, making self-assessment easy and effective.

Download the Science Olympiad Previous Year Paper for Class 10 (PDF) and help your child revise smarter, practice better, and perform their best on exam day.

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Syllabus:

Section 1: Chemical Reactions and Equations, Acids, Bases and Salts, Metals and Non-metals, Carbon and its Compounds, Periodic Classification of Elements, Life Processes, Reproduction in Organisms, Heredity and Evolution, Light-Reflection and Refraction, Human Eye and Colourful World, Electricity, Magnetic Effects of Electric Current, Sources of Energy, Our Environment and its Management.

Achievers Section: Higher Order Thinking Questions - Syllabus as per Section 1

Sample Paper Previous Year Paper Marking Scheme Free Study Material

Previous Year Questions

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Q.2

Q.3

Q.4

Q.5

Q.6

Q.7

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Q.10

Q.1	The Red Data Books published by the International Union for Conservation of Nature and Natural Resources (IUCN) contains lists of which of the following?
	a) Endemic plant and animal species present in the biodiversity hot spots.		b) Threatened plant and animal species
	c) Protected sites for conservation of nature and natural resources in various countries.		d) None of the above

Q.2	What happens when aqueous sodium carbonate (Na2CO3) reacts with HCl(aq)?
	a) NaOH, H2(g) and CO2(g) is formed		b) NaCl, H2O and CO2(g) is formed
	c) NaHCO3, H2(g) and CO2(g) is formed		d) NaHCO3, HO2, (g) and CO2(g) is formed

Q.3	Consider the following statements and choose the correct option: I. Photolysis of water involves the breakdown of water by light. II. The specific function of light energy in the process of photosynthesis is to activate chlorophyll. III. One of the by-product of photosynthesis is oxygen.
	a) Only I is correct		b) Only II is correct
	c) Only III is correct		d) I, II and III are correct

Q.4	In the following question, an assertion and a reason are given. Choose the correct option: Assertion: Atomic size decreases as we move from left to right in a period. Reason: In a period from left to right, the number of valence electrons in the same shell increases.
	a) Both assertion and reason are CORRECT and reason is the CORRECT explanation of the assertion.		b) Both assertion and reason are CORRECT, but reason is NOT THE CORRECT explanation of the assertion.
	c) Both assertion and reason are INCORRECT.		d) Assertion is CORRECT, but reason is INCORRECT.

Q.5	The ciliary muscles can change the focal length of the eye lens. Find the ratio of the focal length of the eye lens when it is focused on two different objects, one at a distance of 2 m and the other at a distance of 1 m. The diameter of the normal eye is 2.5 cm.
	a) 82 : 81		b) 81 : 82
	c) 78 : 81		d) 81 : 78

Q.6	Arrange the following compounds in the decreasing order of covalency of the non-metallic elements: A) PCl5 B) NCl3 C) CH4 D) SO3 E) Cl2O7
	a) EDACB		b) BCADE
	c) ECADB		d) BDACE

Q.7	Which among the following is the correct increasing order of pH found in human body?
	a) Gastric juice, saliva, blood		b) Blood, saliva, gastric juice
	c) Saliva, blood, gastric juice		d) Gastric juice, blood, saliva

Q.8	Concave and convex lenses are placed touching each other. The ratio of magnitudes of their powers is 2:3. The focal length of the system is 30 cm. hen the focal lengths of individual lenses are ________.
	a) -75 cm, 50 cm		b) -15 cm, 10 cm
	c) - 50 cm, 100 cm		d) 40 cm, -200 cm

Q.9	Consider the following statement: 1. A person with myopia can see distant objects distinctly but cannot see nearby objects clearly. 2. A person with hypermetropia cannot see distant objects clearly. 3. A person with presbyopia can see nearby objects without corrective glasses. Which of the statement given above is/are not correct?
	a) 1, 2 and 3		b) 1 and 2 only
	c) 2 and 3 only		d) 3 only

Q.10	The following are the ions obtained by the dissociation of different salts. Which of the following is not possible?
	a) Disodium potassium phosphate → Na+, K+, PO4-3		b) Sodium argentocyanide → Na+, Ag+, CN-
	c) Potash alum → K+, Al+3, SO4-2		d) Bleaching powder → Ca+2, Cl-, OCl-

Your Score: 0/10

Additional Preparation Resources

Students can also refer to the following resources to level up their CREST Science Olympiad (CSO) exam preparation for class 10 -

1. CREST Science Worksheets Package for class 10 - It is a package of 5 worksheets. The worksheets are in the same pattern as the previous year paper. Hence, very useful for preparation. Existing users can purchase additional practice worksheets by following these steps: Login at https://www.crestolympiads.com/login -> Dashboard -> Additional Practice -> Buy & new users can visit https://www.crestolympiads.com/registration
2. CREST Science Olympiad book for class 10 - The book covers topic-wise reading material, chapter-wise practice questions with answer key & contains the previous year paper. The book is available in both physical and pdf formats. Proceed now to purchase the Olympiad book. Also, students can view & download the first chapter of the Science Olympiad book for class 10 for free.

Note: Don’t forget to download the CREST Science Olympiad past year paper pdf for class 10.