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

Q.1

Q.2

Q.3

Q.4

Q.5

Q.6

Q.7

Q.8

Q.9

Q.10

Q.1	Fill in the blank: White light while passing through a glass prism breaks up into light of different colours, because __________.
	a) the refractive index of glass is different for different colours of light		b) glass prism absorbs white light and emits lights of several colours in different directions
	c) of total internal reflection of white light on surfaces of the prism		d) of the interference colours inside the prism

Q.2	Read the following clues and identify X: Clue 1: X is embedded in the uterine wall. Clue 2: It secretes hormones such as oestrogen. Clue 3: It acts as a storage of glycogen.
	a) Zygote		b) Embryo's head
	c) Placenta		d) Eggs

Q.3	Which of the following statements is incorrect?
	a) Sodium and potassium are soft and silvery white metals.		b) Sodium and potassium in the air get tarnished due to the formation of a layer of oxide or carbonate.
	c) Sodium and potassium burn in dry oxygen (excess) giving peroxides.		d) Sodium and potassium are kept under kerosene to avoid contact with air and moisture.

Q.4	Fill in the blank: An electric kettle has two thermal coils A and B. When current is passed through A, water in the kettle boils in 6 minutes. When current is passed through B, the same volume of water in the kettle boil in 8 minutes. If both A and B are joined in series and current is passed, water will boil in _______________.
	a) 14 minutes		b) 7 minutes
	c) 24 minutes		d) 28 minutes

Q.5	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-

Q.6	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.7	A solution of sodium carbonate is prepared by dissolving 0.53 g in 100 ml of the solution. To this 200 ml of 0.001 M NaOH is added. What is the pH of the resulting mixture?
	a) 13		b) 12.53
	c) 15		d) 16. 43

Q.8	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.9	Which among the following cannot be used for the preparation of the halogen acid?
	a) 2KBr + H2SO4 (conc.) → K2SO4 + 2HBr		b) 2NaCl + H2SO4 (conc.) → NaHSO4 + HCl
	c) NaHSO4 + NaCl (conc.) → Na2SO4 + HCl		d) CaF2 + H2SO4 (conc.) → CaSO4 + 2HF

Q.10	Which one among the following statements is correct?
	a) All arteries carry oxygenated blood		b) All veins carry oxygenated blood
	c) Except the pulmonary artery, all other arteries carry oxygenated blood		d) Except the pulmonary vein, all other veins carry oxygenated blood

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.