What are ICSE Class 10 Chemistry Half-Yearly Tests?
ICSE Class 10 Chemistry half-yearly tests are school-level mid-year assessments used to check how well a student has understood the Chemistry syllabus taught so far. These papers usually test definitions, chemical equations, observations, numerical problems, electrolysis, analytical chemistry, metallurgy, study of compounds and organic chemistry in a CISCE-style answer format.
Half-yearly papers are not the same as the final board paper. They are set by schools, so the exact duration, chapter coverage and internal marking may vary. Use them as a diagnostic tool: find weak topics, correct presentation errors and practise writing balanced equations and numerical steps without looking at notes.
Download Chemistry Half-Yearly Tests PDF
The table preserves the available Chemistry half-yearly test PDF links from this page. Open each PDF in a new tab, solve it in one sitting, and then mark the paper topic-wise instead of only checking the final score.
| Year | Paper type | Title | |
|---|---|---|---|
| 2026 | Half-yearly Test | Second Term Chemistry | Download |
| 2017 | Half-yearly Test | Hy Chemistry | Download |
Concept Snapshot: Treat the paper as a lab report of your preparation
A Chemistry half-yearly test does not only ask what you remember. It shows whether you can identify the topic, choose the correct reaction, write observations, calculate with units and present the final answer clearly. Think of each mistake as a labelled test tube: one may be a formula error, another may be a colour-observation error, and another may be an incomplete equation.
Paper Pattern Used in These Tests
The available ICSE Class 10 Chemistry Half-Yearly Tests on this page use an 80-mark written-paper style. Section A is compulsory and contains short-answer items such as multiple-choice questions, fill in the blanks, equations, IUPAC names, observations and matching. Section B contains longer questions, and students are usually asked to attempt a fixed number of questions from the options given.
Because half-yearly tests are school papers, do not assume that every school will use the same time limit or the same chapter cut-off. Follow your school circular for the actual test, and use the PDFs here for practice with the style of questions.
| Area tested | Typical question form | What the examiner checks |
|---|---|---|
| Analytical Chemistry | Observation tables and precipitate colours | Correct reagent, colour, solubility in excess and ion identified |
| Mole Concept and Stoichiometry | Empirical formula, percentage composition, gas volume and vapour density | Formula, substitution, arithmetic and unit |
| Electrolysis and Metallurgy | Electroplating, discharge of ions, extraction and refining | Correct electrode, electrolyte, ion movement and electrode reaction |
| Study of Compounds | Preparation, properties and uses of acids and ammonia | Balanced equations and reason-based explanations |
| Organic Chemistry | IUPAC names, structural formulae and reactions of hydrocarbons | Longest chain, functional group, bond type and balanced reaction |
ICSE Class 10 Chemistry Topic Checklist
Use this checklist to revise the main Chemistry areas commonly tested in Class 10 school papers and CISCE-style questions. Textbook editions may divide the same syllabus into slightly different chapter titles, so revise by topic as well as by chapter name.
| Topic group | What to revise | Practice task |
|---|---|---|
| Periodic properties and chemical bonding | Period and group trends, metallic character, non-metallic character, electrovalent and covalent bonding | Predict bond type from electronic configurations such as 2,8,1 and 2,8,7. |
| Acids, bases, salts and analytical chemistry | Action of reagents, colour of precipitates, soluble and insoluble salts | Write observation tables for \text{Fe}^{2+}, \text{Fe}^{3+}, \text{Cu}^{2+}, \text{Zn}^{2+}, \text{Pb}^{2+} and \text{Ca}^{2+}. |
| Mole concept | Relative molecular mass, vapour density, empirical formula, percentage composition and gas volume at STP | Practise n=\frac{\text{given mass}}{\text{molar mass}} and V=n \times 22.4\ \text{L} at STP. |
| Electrolysis | Electrolytes, electrodes, electroplating, acidified water, fused lead bromide and discharge of ions | State the product at anode and cathode with the electrode reaction. |
| Metallurgy | Ores, alloys, extraction of aluminium, role of cryolite, anode renewal and refining | Write why carbon anodes are consumed during aluminium extraction. |
| Study of compounds | Hydrogen chloride, ammonia, nitric acid and sulphuric acid | Memorise preparation, conditions, observations and balanced reactions. |
| Organic chemistry | Alkanes, alkenes, alkynes, alcohols, carboxylic acids, IUPAC names and structural formulae | Draw structures from names and name compounds from structures. |
Important formulae and reactions to keep ready
| Use | Formula or equation |
|---|---|
| Moles from mass | n=\frac{\text{mass}}{\text{molar mass}} |
| Number of particles | N=n \times 6.022 \times 10^{23} |
| Vapour density relation | \text{Molecular mass}=2 \times \text{vapour density} |
| Contact process: catalytic oxidation | 2\text{SO}_2+\text{O}_2 \xrightarrow{\text{V}_2\text{O}_5} 2\text{SO}_3+\text{heat} |
| Oleum formation | \text{SO}_3+\text{H}_2\text{SO}_4 \rightarrow \text{H}_2\text{S}_2\text{O}_7 |
| Dilution of oleum | \text{H}_2\text{S}_2\text{O}_7+\text{H}_2\text{O} \rightarrow 2\text{H}_2\text{SO}_4 |
| Laboratory preparation of ammonia | \(2\text{NH}_4\text{Cl}+\text{Ca(OH)}_2 \rightarrow \text{CaCl}_2+2\text{H}_2\text{O}+2\text{NH}_3\) |
| Action of ammonia on heated lead oxide | 3\text{PbO}+2\text{NH}_3 \rightarrow 3\text{Pb}+3\text{H}_2\text{O}+\text{N}_2 |
How to Use the Half-Yearly Paper for Revision
Do not solve the paper as a casual worksheet. Simulate exam conditions first, then analyse errors topic-wise.
- First attempt: solve the paper without notes and follow the time printed on the PDF or given by your school.
- Second step: mark each wrong answer as one of four types: concept error, equation error, observation error or calculation error.
- Third step: rewrite every wrong chemical equation in balanced form with atom counts checked on both sides.
- Fourth step: make a separate page for salt-analysis colours and electrolysis products; these are easy to confuse under time pressure.
- Final step: reattempt only the wrong questions after two or three days. This shows whether the correction has stayed in memory.
For official syllabus and specimen-paper updates, check the official CISCE website. For related practice on this site, use ICSE Class 10 Chemistry previous year papers and ICSE Class 10 Chemistry sample papers.
Worked Examples from Half-Yearly Test Style
The examples below are original model solutions based on the types of questions seen in the available half-yearly papers and standard ICSE Class 10 Chemistry treatment.
Worked Example 1: Find the empirical formula from percentage composition
Question: A compound contains 87.5\% nitrogen and 12.5\% hydrogen by mass. Find its empirical formula. Given: \text{N}=14, \text{H}=1.
Step 1: Assume 100\ \text{g} of the compound. Then nitrogen mass =87.5\ \text{g} and hydrogen mass =12.5\ \text{g}.
Step 2: Convert each mass into moles.
n(\text{N})=\frac{87.5}{14}=6.25
n(\text{H})=\frac{12.5}{1}=12.5
Step 3: Divide by the smaller mole value, 6.25.
\text{N}:\text{H}=\frac{6.25}{6.25}:\frac{12.5}{6.25}=1:2
Final answer: The empirical formula is \text{NH}_2.
Worked Example 2: Calculate the percentage of phosphorus in calcium phosphate
Question: Calculate the percentage of phosphorus in calcium phosphate, \( \text{Ca}_3(\text{PO}_4)_2 \). Given: \text{Ca}=40, \text{P}=31, \text{O}=16.
Step 1: Find the molar mass of \( \text{Ca}_3(\text{PO}_4)_2 \).
\text{Molar mass}=3(40)+2\{31+4(16)\}
=120+2(31+64)=120+190=310\ \text{g mol}^{-1}
Step 2: Find the mass of phosphorus in one mole of the compound.
\text{Mass of phosphorus}=2(31)=62\ \text{g}
Step 3: Calculate percentage of phosphorus.
\%\ \text{of phosphorus}=\frac{62}{310}\times 100=20\%
Final answer: Percentage of phosphorus in calcium phosphate is 20\%.
Worked Example 3: Vapour density, moles, mass and molecules at STP
Question: The vapour density of a gas Z is 23. Calculate the number of moles, mass in grams and number of molecules in 6.72\ \text{L} of gas at STP.
Step 1: At STP, 1\ \text{mol} of a gas occupies 22.4\ \text{L}.
n=\frac{6.72}{22.4}=0.3\ \text{mol}
Step 2: Use vapour density to find molecular mass.
\text{Molecular mass}=2 \times \text{vapour density}=2 \times 23=46
Step 3: Find the mass of 0.3\ \text{mol}.
\text{Mass}=n \times \text{molar mass}=0.3 \times 46=13.8\ \text{g}
Step 4: Find the number of molecules.
N=0.3 \times 6.022 \times 10^{23}=1.8066 \times 10^{23}
Final answer: Moles =0.3\ \text{mol}, mass =13.8\ \text{g}, molecules =1.8066 \times 10^{23}.
Worked Example 4: Why is sulphur trioxide not directly absorbed in water?
Question: In the manufacture of sulphuric acid by the contact process, why is \text{SO}_3 absorbed in concentrated sulphuric acid instead of water?
Step 1: Direct reaction of \text{SO}_3 with water is highly exothermic and produces a fine mist of sulphuric acid that is difficult to condense.
Step 2: Therefore \text{SO}_3 is first absorbed in concentrated sulphuric acid to form oleum.
\text{SO}_3+\text{H}_2\text{SO}_4 \rightarrow \text{H}_2\text{S}_2\text{O}_7
Step 3: Oleum is then diluted carefully to obtain sulphuric acid of the required concentration.
\text{H}_2\text{S}_2\text{O}_7+\text{H}_2\text{O} \rightarrow 2\text{H}_2\text{SO}_4
Final answer: \text{SO}_3 is not directly absorbed in water because the reaction is too exothermic and forms an acid mist; it is absorbed in concentrated \text{H}_2\text{SO}_4 to form oleum first.
Examiner’s Mindset for Chemistry Answers
In ICSE Class 10 Chemistry answers, marks are usually lost not because the student knows nothing, but because the answer is incomplete. For a numerical, write the formula first, substitute values with units, then calculate. For an equation, balance it and include conditions if they are part of the reaction, such as \xrightarrow{\text{Pt}} for catalytic oxidation of ammonia in the Ostwald process.
For observation questions, the observation and inference must not be mixed. For example, write “dirty green precipitate is formed” as the observation for \text{Fe}^{2+} with alkali; then write the ion identified separately if asked. A colour alone without the reagent often does not show full understanding.
Common Mistakes in ICSE Chemistry Half-Yearly Tests
- Writing unbalanced equations: Always count atoms on both sides. For example, \(2\text{NH}_4\text{Cl}+\text{Ca(OH)}_2 \rightarrow \text{CaCl}_2+2\text{H}_2\text{O}+2\text{NH}_3\) is balanced; missing the coefficient 2 before \text{NH}_4\text{Cl} changes the answer.
- Confusing precipitate colours: \text{Fe}^{2+} gives a dirty green precipitate with alkali, while \text{Fe}^{3+} gives a reddish-brown precipitate. Do not write only “green” or “brown” if the textbook observation is more specific.
- Using plain word equations where symbols are required: If the question asks for a balanced chemical equation, write the formula equation, not only the names of reactants and products.
- Forgetting the role of electrodes in electroplating: The article to be electroplated is connected as the cathode. The plating metal is usually made the anode so that metal ions are supplied to the solution.
- Adding water to concentrated acid: For dilution, add acid slowly to water with stirring. Adding water to concentrated \text{H}_2\text{SO}_4 may cause violent splashing because the process releases heat.
- Skipping units in mole problems: A final mass should be in \text{g}, amount in \text{mol}, gas volume in \text{L}, and particles as a number of molecules or atoms.
Related ICSE Class 10 Chemistry Resources
Use these related pages for a full revision loop: syllabus, notes, solved answers, papers and additional practice.
- ICSE Class 10 syllabus for the subject-wise curriculum structure.
- ICSE Class 10 Chemistry notes for chapter-wise revision.
- ICSE Class 10 Chemistry solutions for worked textbook-style answers.
- ICSE Class 10 Chemistry previous year papers for board-style practice.
- ICSE Class 10 study materials for all subject resources.
Frequently Asked Questions
Are ICSE Class 10 Chemistry Half-Yearly Tests official CISCE papers?
No. ICSE Class 10 Chemistry Half-Yearly Tests are usually school-set papers. CISCE publishes the syllabus and board examination materials, while individual schools decide the half-yearly paper coverage and schedule.
How should I revise Chemistry one week before a half-yearly test?
Revise Chemistry by question type: first equations and observations, then mole concept numericals, electrolysis, metallurgy, study of compounds and organic structures. Solve one PDF under timed conditions and make an error list from it.
Which ICSE Class 10 Chemistry topics commonly appear in half-yearly tests?
Commonly tested areas include analytical chemistry, mole concept, electrolysis, metallurgy, sulphuric acid, nitric acid, ammonia, hydrogen chloride and organic chemistry. The exact chapter cut-off depends on what your school has completed.
How do I avoid losing marks in Chemistry equations?
Write formulae correctly, balance the equation, add conditions where needed and check atom counts on both sides. For example, 2\text{SO}_2+\text{O}_2 \xrightarrow{\text{V}_2\text{O}_5} 2\text{SO}_3 is balanced.
Should I memorise all precipitate colours for ICSE Chemistry?
Yes, but memorise them with the reagent and the ion. For analytical chemistry, write the colour, whether the precipitate dissolves in excess reagent and the ion indicated by the test.
What is the best way to practise mole concept for Chemistry tests?
Write the formula before substituting values. Practise n=\frac{\text{mass}}{\text{molar mass}}, N=n \times 6.022 \times 10^{23}, V=n \times 22.4\ \text{L} at STP and \text{molecular mass}=2 \times \text{vapour density}.