Here are chapter-wise MCQs for CBSE Class 8 Science, ready for 2026-27. They're built to help Class 8 students understand the current exam pattern in Science, and improve how they solve problems.
Why Practice Class 8 Science Objective Questions?
- Answers are explained clearly for every Science question, so the reasoning actually makes sense.
- Strictly based on the 2026 CBSE Science textbook, and guidelines issued by CBSE.
- Includes Class 8 Assertion-Reasoning, Case-based, and Fill-in-the-blanks formats, all built for Science.
- Each Science chapter has its own set, so you can check your understanding topic by topic.
Class 8 Science Question Bank, Chapter by Chapter
Find the newest Science question sets for 2026-27 below. A good way to check your own progress, and catch weak areas early, before exams.
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Quick Practice - Class 8 Science (NCERT Curiosity) Select any chapter below to test your understanding with interactive questions, instant key validation, and model answers. Q1.Which sequence accurately reflects the stages of a scientific investigation? Answer: (a) Observation → Question → Hypothesis → Experiment → Conclusion. Scientific methodology begins with careful observation, formulating a testable hypothesis, testing it through controlled experimentation, and drawing evidence-based conclusions.
Q2.Why is keeping certain variables constant (controlled variables) essential in a fair test? Answer: (c) To ensure that observed changes are solely due to the independent variable. Controlling extraneous variables isolates the specific effect of the factor being tested.
Q3.Which instrument is used to measure the mass of a substance with high precision in a science laboratory? Answer: (b) Digital analytical balance / Beam balance. Digital balances measure mass, whereas a spring balance measures gravitational force (weight).
Q4.When an unexpected observation contradicts a formulated hypothesis, a scientist should: Answer: (d) Analyze the findings, re-evaluate, and refine the hypothesis. Scientific integrity requires adjusting hypotheses based on empirical data rather than manipulating evidence.
Q5.Repeating an experiment multiple times and computing average values helps to: Answer: (a) Minimize experimental errors and improve result reliability. Multiple trials reduce random measurement fluctuations and establish reproducible evidence.
Q1.Which bacterium converts lactose in milk into lactic acid to produce curd? Answer: (b) Lactobacillus. Lactobacillus promotes milk curdling by producing lactic acid, which coagulates milk proteins.
Q2.Alexander Fleming discovered the first commercial antibiotic, Penicillin, from which organism? Answer: (a) Penicillium notatum (a fungus). In 1928, Fleming discovered penicillin produced by the green mold Penicillium notatum, inhibiting bacterial growth.
Q3.Which microorganism is utilized in baking to release carbon dioxide gas that makes bread dough rise? Answer: (c) Yeast (Saccharomyces cerevisiae). Yeast ferments sugars anaerobically, releasing CO2 bubbles that get trapped and cause the dough to expand.
Q4.The female Anopheles mosquito acts as a vector for transmitting which pathogen? Answer: (b) Plasmodium (Malarial protozoan). Female Anopheles carries the protozoan parasite Plasmodium, transferring it through bites.
Q5.Why are viruses considered borderline entities between living and non-living things? Answer: (d) They are inert crystals outside a host, but replicate inside host cells. Viruses lack cellular machinery and only show life processes like reproduction when hijacking host cell mechanisms.
Q1.According to the World Health Organization (WHO), health is defined as: Answer: (a) A state of complete physical, mental, and social well-being. True health integrates physiological fitness, psychological balance, and supportive social relationships.
Q2.Which deficiency disease is caused by an inadequate intake of Vitamin C in the diet? Answer: (c) Scurvy. Vitamin C deficiency causes scurvy, characterized by bleeding gums, skin spots, and impaired wound healing.
Q3.Which of the following is classified as a non-communicable lifestyle disease? Answer: (b) Type 2 Diabetes Mellitus. Type 2 Diabetes is a non-infectious metabolic disorder influenced by dietary habits, physical inactivity, and genetic predisposition.
Q4.Vaccination provides active artificial immunity against pathogenic infections primarily by: Answer: (a) Stimulating production of specific antibodies and memory white blood cells. Vaccines introduce weakened antigens, training the immune system to recognize and neutralize future infections.
Q5.ORS (Oral Rehydration Solution) is administered to patients suffering from acute dehydration to replenish: Answer: (d) Water and essential electrolytes (Sodium, Potassium, Glucose). ORS restores fluid balance and vital electrolytes lost during severe diarrhea and vomiting.
Q1.The heating element in electrical appliances (like toasters and geysers) is made of Nichrome because it has: Answer: (a) High electrical resistivity and a high melting point without oxidizing readily. Nichrome (Nickel-Chromium alloy) produces Joule heating (H = I2Rt) without burning or melting at high temperatures.
Q2.Who first discovered that an electric current flowing through a wire deflects a nearby magnetic compass needle? Answer: (b) Hans Christian Oersted. In 1820, Oersted discovered electromagnetism when a current-carrying wire deflected a magnetic needle.
Q3.An electrical safety fuse functions on which fundamental physical principle? Answer: (c) Heating effect of electric current. When current exceeds safe limits, Joule heating melts the low-melting-point fuse wire, breaking the circuit.
Q4.Which modification increases the magnetic field strength of an electromagnet? Answer: (d) Increasing coil turns and electric current. Magnetic field intensity inside a solenoid is directly proportional to current and the number of turns in the coil.
Q5.What modern automatic electromagnetic switch has largely replaced traditional wire fuses in home wiring? Answer: (a) Miniature Circuit Breaker (MCB). An MCB automatically trips when detecting overcurrent or short circuits and can be reset without replacing components.
Q1.Which of the following is classified as a non-contact force? Answer: (c) Gravitational force. Gravity acts across empty space between masses without requiring physical contact.
Q2.Two equal forces of 25 N act on an object in opposite directions. The net resultant force is: Answer: (a) 0 N (Balanced forces). Equal and oppositely directed forces cancel each other (25 N - 25 N = 0 N).
Q3.What causes dry hair to attract small bits of paper after being combed with a plastic comb? Answer: (b) Electrostatic force. Friction transfers electrons, leaving the comb with an electrostatic charge that attracts neutral paper bits.
Q4.Which statement regarding friction types for the same pair of surfaces is correct? Answer: (d) Static friction (limiting) > Sliding friction > Rolling friction. Interlocking of surface irregularities is strongest at rest, weaker during sliding, and minimal during rolling contact.
Q5.What is the standard SI unit used to measure force? Answer: (a) Newton (N). The SI unit of force is the Newton (N = kg·m/s2).
Q1.Pressure is defined mathematically as force acting per unit area. Its standard SI unit is: Answer: (b) N/m2 (Pascal / Pa). Pressure = Force / Area. 1 Pascal = 1 N/m2.
Q2.Why do sharp cutting knives cut objects much more effectively than blunt knives? Answer: (a) Smaller contact area generates greater pressure for the same applied force. Since pressure is inversely proportional to area, a thin edge produces high cutting pressure.
Q3.According to fluid mechanics principles, liquid pressure inside a vessel: Answer: (c) Increases with depth and exerts equal pressure in all directions at a given depth. Hydrostatic pressure increases with depth and acts equally in all lateral directions.
Q4.The calm, low-pressure central region of a tropical cyclone is called the: Answer: (b) Eye of the cyclone. The eye is a roughly circular area (10–30 km wide) of light winds and fair weather at the cyclone's center.
Q5.High-speed winds blowing over roofs reduce air pressure above them, causing roofs to blow off due to: Answer: (a) High upward net pressure from higher air pressure inside the house (Bernoulli's principle). Fast wind reduces pressure above the roof, creating an upward pressure differential from the trapped air inside.
Q1.The spontaneous intermingling and spreading of particles of two different substances into each other is: Answer: (b) Diffusion. Diffusion is the net movement of particles from regions of higher concentration to lower concentration driven by thermal kinetic energy.
Q2.Which state of matter has a definite volume but no fixed shape, taking the shape of its container? Answer: (a) Liquid. Liquid particles are closely packed enough to maintain constant volume, while sliding past one another to adapt to container shapes.
Q3.What happens to the kinetic energy and movement of constituent matter particles as temperature rises? Answer: (c) Kinetic energy increases and particles move faster. Temperature is a measure of average molecular kinetic energy. Higher heat accelerates random particle motion.
Q4.The process by which a solid changes directly into vapor on heating without passing through a liquid state is: Answer: (d) Sublimation. Substances like camphor, ammonium chloride, and dry ice sublime directly from solid to gas phase.
Q5.Why does sweating cool the human body during hot summer days? Answer: (b) Evaporating sweat absorbs latent heat of vaporization from the skin. Evaporating water molecules draw latent heat away from the body surface, lowering skin temperature.
Q1.A pure substance composed of only one type of atom that cannot be broken down chemically is an: Answer: (a) Element. An element (such as Gold, Oxygen, or Iron) consists of a single type of atom with a uniform atomic number.
Q2.Why is pure water (H2O) classified as a chemical compound rather than a mixture? Answer: (c) Hydrogen and oxygen are chemically bonded in a fixed 1:8 mass ratio with entirely new properties. In a compound, constituent elements combine chemically in fixed proportions by mass, yielding distinct properties from the original elements.
Q3.Which of the following is an example of a non-metal that exists as a liquid at room temperature? Answer: (b) Bromine (Br2). Bromine is the only non-metallic element that is liquid at standard temperature and pressure (Mercury is a liquid metal).
Q4.Which method is suitable for separating iron filings from a mixture with sulfur powder without heating? Answer: (a) Magnetic separation. In a physical mixture, iron retains its magnetic properties and can be separated using a bar magnet.
Q5.Tincture of iodine, used as an antiseptic, is prepared by dissolving: Answer: (d) Solid iodine in alcohol (ethanol). Tincture of iodine is a true solution containing 2–7% elemental iodine dissolved in ethanol and water.
Q1.In an aqueous solution containing 10 g sugar completely dissolved in 100 g water, water acts as the: Answer: (b) Solvent. The component present in greater quantity that dissolves the other substance is the solvent; the dissolved substance is the solute.
Q2.A solution in which no more solute can dissolve at a specific given temperature is called a: Answer: (a) Saturated solution. A saturated solution holds the maximum concentration of dissolved solute in thermodynamic equilibrium at that temperature.
Q3.What is the mass percentage concentration of a solution prepared by dissolving 25 g salt in 175 g water? Answer: (c) 12.5%. Mass % = [25 / (25 + 175)] × 100 = (25 / 200) × 100 = 12.5%.
Q4.How does the solubility of common solid solutes (like copper sulphate or sugar) generally change when water temperature increases? Answer: (a) Solubility increases. Higher thermal energy increases solvent intermolecular spaces and solute kinetic dissociation, increasing solid solubility.
Q5.Why is water universally recognized as the "Universal Solvent"? Answer: (d) Its high polarity and dielectric constant dissolve a broader range of substances than any other liquid. Water's polar structure weakens ionic bonds and readily hydrates solute molecules.
Q1.What is the nature and orientation of the image formed by a standard plane mirror? Answer: (b) Virtual, erect, same size as object, and laterally inverted. Plane mirrors produce virtual images situated at equal distances behind the reflecting surface.
Q2.Which type of mirror is used as a rear-view mirror in motor vehicles to provide a wider field of view? Answer: (c) Convex mirror. Convex mirrors curve outward, always forming erect, diminished virtual images with a broader viewing field.
Q3.Where must an object be placed in front of a concave mirror to obtain a virtual, magnified, and erect image? Answer: (a) Between the Pole (P) and the Principal Focus (F). Dentists use concave mirrors in this configuration to examine magnified images of teeth.
Q4.A transparent optical lens that is thicker at the centre than at the edges is a: Answer: (b) Convex lens (Converging lens). Convex lenses converge parallel rays of light toward a real focal point.
Q5.The splitting of white light into its seven constituent colors when passing through a glass prism is called: Answer: (d) Dispersion of light. Different wavelengths refract by varying degrees in glass, separating white light into the VIBGYOR spectrum.
Q1.What ancient astronomical timekeeping device measures solar time by the position of a shadow cast on a calibrated dial? Answer: (b) Sundial (Gnomon). Sundials use the sun's apparent motion to cast shadows indicating solar time, such as at the Jantar Mantar observatories.
Q2.The periodic occurrence of seasonal cycles on Earth is caused by: Answer: (a) Earth's revolution around the Sun along with its tilted rotational axis (23.5°). Axial tilt alters solar illumination angle and day length throughout the orbital period, creating seasons.
Q3.Why does the Pole Star (Polaris) appear stationary in the northern night sky throughout the year? Answer: (c) It lies almost directly along the line of Earth's northern axis of rotation. Because Polaris aligns with Earth's rotational axis, Earth's daily spin does not change its apparent position.
Q4.The time taken by the Moon to complete one cycle of lunar phases from new moon to new moon (synodic month) is approximately: Answer: (b) 29.5 days. The synodic lunar period is approximately 29.5 days, forming the basis of historical lunar calendar systems.
Q5.Which famous historical astronomical observatory in India was constructed by Maharaja Jai Singh II? Answer: (d) Jantar Mantar (Jaipur and Delhi). Sawai Jai Singh II built stone astronomical observatories in Jaipur, Delhi, Ujjain, Varanasi, and Mathura.
Q1.In a biological food chain (e.g., Grass → Deer → Tiger), green plants occupy which trophic level? Answer: (a) First trophic level (Primary Producers). Autotrophic green plants convert radiant solar energy into chemical food via photosynthesis, forming the base of ecological food chains.
Q2.What proportion of energy is transferred from one trophic level to the next in Lindeman's Efficiency Law? Answer: (b) Approximately 10%. About 90% of captured energy is lost as heat and used during respiration/metabolism, leaving roughly 10% available for the next consumer level.
Q3.A symbiotic ecological relationship in which both cooperating organisms benefit mutually is termed: Answer: (c) Mutualism (e.g., Lichens, Pollinators). Mutualism benefits both species, as seen in lichens where fungi provide minerals and algae perform photosynthesis.
Q4.What is the ecological role of saprotrophic decomposers (bacteria and fungi) in natural ecosystems? Answer: (d) Breaking down dead organic matter and recycling nutrients back into soil. Decomposers break down organic waste into inorganic mineral nutrients that producers can reuse.
Q5.The increasing concentration of non-biodegradable toxic chemicals (like pesticides) at higher trophic levels is: Answer: (a) Biological Magnification (Biomagnification). Non-biodegradable toxins accumulate in fatty tissues and increase in concentration at each successive trophic level.
Q1.Earth resides in the circumstellar habitable zone of our Solar System, often termed the: Answer: (b) Goldilocks Zone. The Goldilocks zone provides surface temperatures that are neither too hot nor too cold, allowing liquid water to persist.
Q2.What critical role does Earth's molten iron-nickel outer core play in sustaining the biosphere? Answer: (a) It generates the geomagnetic field (magnetosphere) that shields Earth from harmful solar wind. Dynamo action in the liquid outer core creates a magnetic shield deflecting ionizing cosmic particles.
Q3.The stratospheric ozone layer (O3) is vital for terrestrial life because it absorbs: Answer: (c) Harmful ultraviolet-B and ultraviolet-C solar radiation. Ozone filters out high-energy UV radiation that damages DNA and cellular structures.
Q4.The four interconnected global spheres that form Earth's life support system are the: Answer: (d) Lithosphere, Hydrosphere, Atmosphere, and Biosphere. Earth operates as an interconnected system through soil (lithosphere), water (hydrosphere), air (atmosphere), and life (biosphere).
Q5.The natural greenhouse effect in Earth's atmosphere is essential for life because it: Answer: (b) Traps re-radiated heat, maintaining an average global temperature of ~15°C instead of a frozen -18°C. Natural greenhouse gases (H2O vapor, CO2, CH4) maintain thermal conditions needed for liquid water and life.
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FAQs
For the 2026-27 session, MCQs and objective-type questions carry around 20% weightage. CBSE has introduced 30% competency based questions as MCQs and they are important part of the Class 8 Science paper.
You can access the latest chapter-wise MCQs for Class 8 Science for free from StudiesToday.com. All questions are based on the latest syllabus and current academic year.
Yes, our Science practice bank includes the new pattern of Assertion Reasoning and Case Study based MCQs. They have been designed to test the analytical skills of Class 8 students.
Solving Class 8 Science MCQs regularly improves speed and accuracy as these are objective questions can get you 100% marks if your understanding of the topic is clear.
Yes, all Class 8 Science MCQs and answers are accessible on any device at your convenience.
No, all Science Multiple Choice Questions (MCQs), practice papers, and solutions for Class 8 are available for free for students to get more marks school exams.