CBSE Board Exam 2026: Science Sample Paper Questions With Revised Pattern

The CBSE Science exam for 2026 now has a changed format where the whole paper is divided into Biology, Chemistry and Physics sections. Students get direct and clear questions from each part, and the marking pattern is simpler than earlier. The sample paper already shows how CBSE wants short and clear answers from students, with more real-life based questions. The exam begins from February 17, so this new structure matters for scoring high in the coming board. The fresh format helps students focus on each subject area separately and understand how to attempt every part with confidence.

CBSE Science Paper 2026 Comes With A Section-Based Pattern

The new Science pattern splits the full question paper into three fixed sections. Biology becomes Section A, Chemistry becomes Section B, and Physics becomes Section C. Students do not need to mix concepts while writing answers because each part is already organised. CBSE shared this model to reduce confusion and make the answer sheet neat for both students and teachers. The latest circular explains that each section may carry different formats but all follow simple, direct questioning.

Biology Section With Rephrased Questions And Answers

In Biology, CBSE has asked more understanding-based questions. One question asks why plants do not form excretory waste the way animals do. The simple answer is that plants produce very little waste because their food creation process is different, and most by-products are reused inside the plant itself.

Another question compares the number of heart chambers in fish and humans and how mixing of oxygen-rich and oxygen-poor blood is stopped. Fish have two chambers, humans have four, and the separation of chambers ensures that the two types of blood do not mix.

A transportation-of-water question asks the basic mechanism. The answer is that water moves upward in plants mainly through transpiration pull, root pressure and capillary action.

A reserve-forest food chain question appears too. Students have to create two food webs using animals like rabbit, frog, fox, birds, tiger and others. The idea is to show how energy flows from producers like grass and trees to consumers.

Another question describes how nerve cells pass messages. The answer is that impulses travel through electrical signals inside the neuron and then move across synapses through chemical signals.

The genetics question with round green (RRyy) and wrinkled yellow (rrYY) seeds asks students to show possible gametes and the ratio of traits in 144 plants. When F1 plants self-pollinate, they form gametes like Ry and rY, and the final saplings show a classic dihybrid ratio pattern.

The digestion question with sweet potatoes and eggs asks which food gives more protein and where protein digestion starts. Eggs have more protein, and its digestion begins in the stomach with enzymes like pepsin under acidic conditions.

The banana plant reproduction question asks whether banana grows by seeds or other methods. The rephrased answer explains that bananas usually grow by vegetative propagation because seed growth is not common. It also says small variations happen due to genetic changes and sometimes these variations can even help plants survive different conditions.

Chemistry Section With Rephrased Questions And Answers

One Chemistry question talks about an element kept in kerosene that cannot be extracted with a reducing agent and forms an ionic compound with chlorine. The answer shows that the element cannot be stored in water because it reacts strongly. The element is sodium, and it is extracted by electrolysis of molten sodium chloride.

Another question explains why copper domes become green, even though copper is reddish. The green shade appears because copper reacts with air and forms a protective layer. Replacing copper with iron is not ideal because iron rusts faster. Ancient builders chose copper because it was easy to shape and lasted long.

A neutralisation experiment with NaOH and H₂SO₄ tests colour change with phenolphthalein. If concentrated acid is used, fewer drops are needed. If 3 mL of acid changes the colour, students must estimate how much base was present earlier. The equation shows the neutralisation between sodium hydroxide and sulphuric acid and the question confirms that the reaction is both a neutralisation and double displacement.

Another Chemistry question gives a hydrocarbon formula and asks to find x and y. Solving the equation shows the compound is propane. Students must name the alcohol that produces this compound when dehydrated, draw its dot structure and write its hydrogenation reaction.

Physics Section With Rephrased Questions And Answers

A Physics question asks students to find the area and length of a copper wire needed for a 0.12Ω resistor. Students must use the resistivity formula. By substituting values, they calculate the area using diameter and then the required length.

Another question explains why household appliances are connected in parallel but only the fuse is in series. The answer is that parallel wiring lets every device get the same voltage, while the fuse in series protects the whole circuit. With a heater of 1500W and fan of 500W on a 220V line, students calculate the total current and check if a 10A fuse is safe.

The alternate problem with two resistors in parallel asks for total heat developed in five minutes. Students check whether each resistor stays within safe power limits.