ICSE Class 10 Chemistry Paper Pattern 2027 and Chapter-wise Weightage

Whichever four Section B questions you pick, you still meet study of compounds and a mole-concept sum. In 2025 and 2026 no choice of four brought study of compounds below 14 marks.

TL;DR

• 80 marks in two hours plus 15 minutes of reading; Section A 40 compulsory, Section B any four of six.
• Largest chapters in my count for 2025, 2026 and the 2027 specimen: study of compounds (22, 21, 17) and organic chemistry (15, 18, 19).
• Equation marks rose from 9 and 10 to 16 in the specimen (17 if a mixed ratio-and-equation part counts in full).
• The exam is on Friday 12 March 2027 at 10:15 a.m.

What is the ICSE Class 10 Chemistry paper pattern for 2027?

CISCE's ICSE 2027 Chemistry syllabus sets Science Paper 2 (code 522 on the question papers) as one two-hour paper of 80 marks, with internal assessment of practical work for 20. The instructions on page 1 of the 2025 and 2026 papers and the 2027 specimen are word for word the same, and all three papers share this frame:

• No writing in the first 15 minutes, which are reading time.
• Section A, 40 marks, compulsory: Question 1 has 15 one-mark MCQs and Question 2 has five blocks of 5 marks.
• Section B, 40 marks: any four of Questions 3 to 8, 10 marks each.
• The internal 20 marks, as per the syllabus: 10 from your subject teacher and 10 from an external examiner, marked independently.

CISCE's ICSE 2027 timetable, dated 10 November 2026, puts Chemistry on Friday 12 March 2027 at 10:15 a.m., between Physics on 8 March and Biology on 15 March. Reading time starts at 10:00 a.m. and you must be seated by 9:45 a.m.

So you write 40 compulsory marks and four of six 10-mark questions, on 12 March 2027.

How were the 2025 and 2026 papers and the 2027 specimen built?

The frame stayed fixed. The parts inside it moved:

• Question 1 had 15 MCQs each time: two assertion-reason items in 2025 and 2026, and one assertion-reason plus one two-statement item in the specimen.
• Question 2 always had a diagram block (ammonia from aluminium nitride in 2025, the Haber process in 2026, electrolysis of acidulated water in the specimen), fill in the blanks and organic chemistry.
• The board papers had a block for naming terms. The specimen has a block of five balanced equations instead.
• Section B: in 2025 and 2026, five questions had parts of 2, 2, 3 and 3 marks and one had parts of 3, 3 and 4. The specimen has three questions of each kind, so it prints 21 parts against 23.

The 2026 redox match returns in the specimen with one line changed: the oxide ion half-equation now reads 2O²⁻ - 4e⁻ → O₂, which balances, where 2026 printed 2e⁻. Our ICSE Class 10 Chemistry past papers post sets out how the specimen differs from the 2026 paper.

Same rubric in all three; the specimen swaps the naming block for five equations.

What is the chapter-wise weightage of ICSE Class 10 Chemistry?

CISCE does not publish one. The 2027 syllabus lists nine units and puts no marks against them; our ICSE Class 10 Chemistry syllabus post lists what each unit covers.

I counted every marked part of CISCE's 2025 and 2026 ICSE Chemistry papers and the 2027 specimen, gave each to one of the nine syllabus chapters, and checked the totals add to 40 in Section A and 10 in every Section B question. Where a part mixed two chapters, the marks went to the chapter whose syllabus line names that reaction. I counted the 5-mark match on oxidation, reduction and ionisation under electrolysis, along with the parts on electrolytes, ions and molecules, because the syllabus teaches them there (unit 6), and the molten alumina MCQ under metallurgy.

Printed marks out of 100 (Section A plus all six Section B questions), for 2025, 2026 and the 2027 specimen:

• Study of compounds (hydrogen chloride, ammonia, nitric acid, sulphuric acid): 22, 21, 17.
• Organic chemistry: 15, 18, 19.
• Periodic properties: 11, 13, 10.
• Electrolysis: 8, 16, 11.
• Mole concept and stoichiometry: 12, 10, 9.
• Analytical chemistry: 13, 6, 10.
• Acids, bases and salts: 8, 8, 10.
• Chemical bonding: 6, 5, 7.
• Metallurgy: 5, 3, 7.

Source: CISCE ICSE 2025 and 2026 Chemistry (Science Paper 2) question papers and ICSE 2027 specimen paper, Gradehunt count.

Section A touched all nine chapters every time. Organic chemistry took exactly 10 of Section A's 40 marks in 2025 and 2026, and 8 in the specimen. Other rules for mixed parts can move a chapter by several marks. Electrolysis in 2026 is the biggest case: 16 by my rules, but 9 if the 5-mark redox match and the three 1-mark parts on electrolytes, ions and molecules are counted elsewhere and the molten alumina MCQ is counted here.

Study of compounds and organic chemistry were the two largest chapters in all three papers, with 37, 39 and 36 marks between them.

Which chapters can you not skip in Section B?

I ran all 15 ways of picking four of the six Section B questions. Lowest and highest marks per chapter in your 80, for 2025, 2026 and the specimen:

• Study of compounds: 14-22, 14-21, 7-17.
• Organic chemistry: 10-15, 12-18, 8-19.
• Periodic properties: 6-11, 5-13, 4-10.
• Electrolysis: 3-8, 10-16, 11 in every choice.
• Mole concept: 5-12, 5-10, 4-9.
• Analytical chemistry: 6-13, 2-6, 3-10.
• Acids, bases and salts: 2-8, 2-8, 5-10.
• Chemical bonding: 2-6, 4-5, 2-7.
• Metallurgy: 3-5, 1-3, 3-7.

Source: CISCE ICSE 2025 and 2026 Chemistry papers and the 2027 specimen, Gradehunt count of all 15 choices.

Mole-concept sums sat in exactly three of the six Section B questions in each paper (2025: Questions 3, 4 and 6; 2026: 4, 6 and 8; specimen: 5, 6 and 7). You skip only two, so one sum is always in your four.

Electrolysis went the other way in the specimen. All 11 of its marks are in Section A, while in 2026, 7 electrolysis marks were in Section B.

Skip any two Section B questions and you still write a mole-concept sum; in 2025 and 2026 study of compounds never fell under 14 of your 80.

How many marks go to equations and numericals?

These counts do not depend on the chapter rules. They cover the whole printed paper, all six Section B questions included. For 2025, 2026 and the specimen:

• Balanced equations: 9 marks (1 in Section A), 10 (none in Section A) and 16 (6 in Section A). I counted one of the two marks in specimen Question 7(i), which also asks a ratio.
• Mole-concept numericals: 11, 9 and 9 marks, 2 of them in Section A each time.
• Dot and dot-and-cross structures: 3, 1 and 5 marks. The specimen asks for a lab compound written as H₂P, where P is a non-metal (hydrogen sulphide fits), and for NH₄⁺ with its coordinate bond and the N₂ molecule.

Source: CISCE ICSE 2025 and 2026 Chemistry papers and the 2027 specimen with draft marking scheme, Gradehunt count.

The draft marking scheme with the 2027 specimen marks the Question 2 equations block as five single marks, so one wrong equation there costs one mark.

Equation marks went up to 16 in the specimen while numericals held at 9 to 11.

How much of the paper tests application?

Every specimen part has a skill tag. Over the 100 printed marks, Application has 50, Understanding 20, Recall 19 and Analysis 11; Evaluation and Create have none.

In Section A, Application and Analysis take 22 of 40 marks (55%). In the 80 marks you write, your choice of four Section B questions puts them at 45 to 51 (56% to 64%).

Source: skill tags printed in the CISCE ICSE 2027 Chemistry specimen, Gradehunt count.

CISCE's circular of 9 October 2026, covered in our ICSE specimen papers for 2027 post, puts higher-order skills at about 50% and says board papers may not be identical in format or content to the specimen.

More than half the marks you write in the specimen carry an Application or Analysis tag, whichever four Section B questions you choose.

How I would prepare with these numbers

1. Revise study of compounds and organic chemistry first: 37, 39 and 36 marks together.
2. Do one mole-concept sum a day until 12 March.
3. Write the reactions of the four named compounds as balanced equations, five at a time.
4. Before 12 March, time yourself on the 2025 and 2026 papers. In the reading time, check which of your four Section B picks carries a mole sum.

Our 10 Years Solved Papers (PYQ) for ICSE Class 10 has older Chemistry papers with solutions, arranged chapter-wise. Physics comes four days before Chemistry; our ICSE Class 10 Physics paper pattern post covers it.

If you want a full Chemistry paper checked before 12 March, the Gradehunt ICSE Class 10 test series has you write by hand and upload, and subject experts check the copy within 48 hours of upload.