O Level & IGCSE Datesheet May–June 2026 (Zone 4): Download Full CAIE Final Timetable PDF
Get the latest O Level & IGCSE Datesheet May–June 2026 (Zone 4) right here! Download the official CAIE final timetable PDF for all Cambridge subjects — plan your exams, track paper timings, and even create your own custom study schedule online.
Introduction: Cambridge O Level & IGCSE Datesheet May–June 2026 (Zone 4)
The long-awaited O Level & IGCSE Datesheet for May–June 2026 (Zone 4) is finally here! Every year, thousands of Cambridge students across Asia, Africa, and the Middle East eagerly await this official release from Cambridge Assessment International Education (CAIE) — and 2026 is no exception. The timetable outlines every written, practical, and oral exam for both IGCSE and O Level candidates, helping students plan their study schedules with confidence.
This year’s CAIE May–June 2026 Exam Series officially begins on Thursday, 23 April 2026, and runs until Tuesday, 9 June 2026, covering all major subjects including English Language, Mathematics, Physics, Chemistry, Biology, Islamiyat, Pakistan Studies, Computer Science, and Business Studies. Zone 4 — which includes countries such as Pakistan, UAE, India, Bangladesh, Sri Lanka, and several others — follows this specific schedule, so it’s crucial for every candidate to align their preparations accordingly.
The final version of the CAIE timetable (Version 1, October 2025) has now been confirmed and published by Cambridge International. Unlike the provisional versions, this official release includes the definitive paper codes, session timings (AM/PM/EV), and dates. Students can now download the complete Zone 4 PDF or view the subject-by-subject schedule directly from this page.
To make it even more convenient, this guide will not only give you the entire May–June 2026 datesheet but also show you how to create your personalized timetable by selecting your subjects. Whether you’re a private candidate, a school student, or a teacher coordinating multiple entries, this organized timetable will help you track every paper in detail.
In the next sections, you’ll find:
A clear explanation of how the CAIE exam structure works for both O Level and IGCSE.
The complete weekly schedule (April–June 2026).
Direct download link for the final CAIE PDF (Zone 4).
A guide to building your own subject-wise study plan.
And most importantly, expert tips to prepare effectively for your upcoming CAIE exams.
So, let’s get started and explore the Cambridge O Level & IGCSE Datesheet for May–June 2026 (Zone 4) in full detail below — including how to download it and customize it for your personal exam setup.
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Understanding the CAIE Exam Structure for 2026
Before diving into the full O Level & IGCSE Datesheet for May–June 2026 (Zone 4), it’s essential to understand how Cambridge Assessment International Education (CAIE) structures its global examination system. Each year, Cambridge runs two major sessions — May–June and October–November — across various administrative zones. These zones, numbered 1 to 6, ensure that time differences and regional logistics are managed efficiently while maintaining identical international standards.
What Is “Zone 4” in CAIE Exams?
“Zone 4” refers to one of the key administrative regions used by Cambridge to group countries that share similar local times and school calendars. This zone primarily includes nations such as Pakistan, United Arab Emirates, India, Bangladesh, Sri Lanka, Nepal, and the Maldives. If you are a student in any of these countries, the official Zone 4 datesheet applies to you.
Cambridge ensures that every zone’s exam timing is aligned with its Key Time Regulations — the designated moments during which all students worldwide either start or remain under supervision. These regulations prevent information leaks between different time zones and preserve fairness for everyone taking the same subject.
Exam Sessions and Paper Codes
The CAIE May–June 2026 session is divided into three distinct daily slots:
AM – Morning Session (usually starting between 8:00 a.m. and 9:00 a.m.)
PM – Afternoon Session (typically between 1:00 p.m. and 2:00 p.m.)
EV – Evening Session (used mainly for longer or overflow exams)
Every subject has one or more papers, each labeled by a unique component code. For instance:
IGCSE Physics (0625/32) → Paper 3, Core Practical Exam
O Level Mathematics (4024/22) → Paper 2, Extended Written Exam
These codes allow schools and candidates to identify exactly which exam they are entered for. The official CAIE timetable lists these codes beside the corresponding date, duration, and session.
Key Time and Supervision Rules
Cambridge’s strict Key Time Policy requires all candidates in the same zone to be under Full Centre Supervision at a specific time each session. If your exam begins later than the key time, you must remain supervised — without digital devices — until your paper starts. Likewise, if you finish early, you stay under supervision until the key time passes. This system maintains exam integrity worldwide.
Difference Between IGCSE and O Level
Although both IGCSE and O Level qualifications are internationally recognized, they serve slightly different purposes:
IGCSE focuses on modern assessment approaches, offering coursework options, a wider range of subjects, and flexibility for international contexts.
O Level follows a more traditional pattern, preferred in regions like South Asia and the Middle East, emphasizing written assessments and clear grading boundaries.
Despite these variations, both levels open doors to higher education, A Levels, or equivalent qualifications. Their 2026 May–June timetables often run side by side, which is why this article provides a unified guide for both streams.
Full O Level & IGCSE Datesheet May–June 2026 (Zone 4)
The Cambridge O Level & IGCSE Datesheet for May–June 2026 (Zone 4) is the official and final timetable released by Cambridge Assessment International Education (CAIE). This version confirms the definitive exam schedule for all students in Pakistan, UAE, India, Bangladesh, Sri Lanka, and neighboring regions under Zone 4.
According to the final timetable (Version 1, October 2025), the exams start on Thursday, 23 April 2026, and conclude on Tuesday, 9 June 2026. The schedule includes written, listening, practical, and multiple-choice papers, ensuring that every subject component is properly covered.
Below is a structured weekly summary of the May–June 2026 exams for both O Level and IGCSE students:
📅 Week 1: 23–24 April 2026
Highlights:
Islamiyat (O Level 2058/12) – AM session
IGCSE French 0520/42, Mandarin Chinese 0547/42 – AM session
O Level Islamic Studies 2068/12, Bengali 3204/01, Tamil 3226/01 – PM session
AS Marine Science 9693/12 – PM session
This week marks the beginning of the CAIE season, with most initial papers focused on languages and religious studies.
📅 Week 2: 27 April – 1 May 2026
Key Exams:
O Level English Language 1123/22 – AM session (27 April)
IGCSE Mathematics (Core & Extended) – AM (27 April)
Pakistan Studies (O Level 2059/01, IGCSE 0448/01) – PM (28 April)
O Level Mathematics D 4024/12 – PM (29 April)
IGCSE Biology 0610/32, Chemistry 0620/32 – AM sessions
AS Global Perspectives 9239/12 – AM (30 April)
By the end of April, major core subjects like Maths, English, Chemistry, and Biology begin, signaling the heart of the exam phase.
📅 Week 3: 4 – 8 May 2026
Key Exams:
O Level Physics 5054/22 – AM (4 May)
O Level Pakistan Studies 2059/02 – PM (4 May)
IGCSE Islamiyat 0493/22 – AM (5 May)
O Level Maths D 4024/22 – PM (5 May)
IGCSE Global Perspectives 0457/12 – PM (6 May)
O Level History 2147/12 – PM (7 May)
IGCSE Physics 0625/32, 0625/42 – AM (8 May)
During this week, science and humanities papers dominate the schedule — particularly Physics, History, and Pakistan Studies.
📅 Week 4: 11 – 15 May 2026
Key Exams:
O Level Business Studies 7115/12 – AM (11 May)
IGCSE Literature in English 0475/22, 0475/32, 0475/42 – PM (11 May)
O Level Computer Science 2210/12 – AM (13 May)
O Level History 2147/22 – PM (15 May)
IGCSE Sociology 0495/12 – PM (15 May)*
This week represents a balanced mix of literature, science, and business subjects — ideal for students across all disciplines.
📅 Week 5: 18 – 22 May 2026
Key Exams:
O Level Additional Mathematics 4037/12 – AM (18 May)
O Level Accounting 7707/22, Computer Science 2210/22 – AM (20 May)
O Level Economics 2281/22 – AM (22 May)
IGCSE Travel & Tourism 0471/22 – PM (19 May)
IGCSE Arabic (0544/42) – PM (22 May)*
This week is crucial for Commerce and Science students, featuring major subjects like Accounting, Economics, and Computer Science.
📅 Week 6: 25 – 29 May 2026
Key Exams:
IGCSE Additional Mathematics 0606/22 – AM (26 May)
O Level Sociology 2251/22 – PM (26 May)
O Level Commerce 7100/22 – PM (28 May)*
By the end of May, most core and elective papers are wrapping up. Only multiple-choice and practicals remain.
📅 Week 7: 1 – 5 June 2026
Key Exams:
O Level Economics (Multiple Choice) 2281/12 – AM (5 June)
O Level Food & Nutrition 6065/12 – PM (5 June)*
IGCSE Environmental Management 0680/22 – AM (1 June)*
This week covers the final written papers and practical components.
📅 Week 8: 8 – 9 June 2026 (Final Week)
Key Exams:
O Level Biology (Multiple Choice) 5090/12 – AM (8 June)*
O Level Chemistry (Multiple Choice) 5070/12 – AM (9 June)*
This marks the conclusion of the CAIE May–June 2026 session, officially ending the examination period for Zone 4 candidates.
🧾 Note:
You can download the full official PDF version of this timetable (including all subject codes and durations) from the Cambridge International Timetables Portal:
https://www.cambridgeinternational.org/timetables
How to Download the Official CAIE Datesheet PDF (Zone 4)
Getting your hands on the official O Level & IGCSE Datesheet for May–June 2026 (Zone 4) is quick and easy. Cambridge Assessment International Education (CAIE) releases verified PDF versions of each timetable to ensure accuracy and authenticity for all registered centres and private candidates.
Whether you’re studying privately or through an affiliated school, follow the steps below to download the final Zone 4 PDF directly from the Cambridge portal — or through trusted platforms such as CambridgeClassRoom.com (based on the same official data).
Step-by-Step Guide to Download the Official CAIE PDF
1. Visit the Cambridge Timetables Page
Go to the official website:
👉 https://www.cambridgeinternational.org/timetables
This is the official source where CAIE publishes final versions of all timetables, grouped by session (May–June, October–November, and March series).
2. Choose the “June 2026” Series
Select the “June 2026” examination session from the list. You’ll see several downloadable files categorized by Zone (1–6) and qualification level (IGCSE, O Level, AS & A Level).
3. Select “Administrative Zone 4”
Click on Zone 4, which applies to candidates in:
🇵🇰 Pakistan, 🇮🇳 India, 🇧🇩 Bangladesh, 🇱🇰 Sri Lanka, 🇦🇪 UAE, 🇳🇵 Nepal, and other surrounding countries under this time zone.
This ensures you’re viewing the correct time slots and exam dates according to your region.
4. Download the Final Timetable PDF
Click the link titled:
🗂️ “Cambridge International June 2026 Final Timetable – Zone 4 (Version 1, October 2025)”
This PDF includes all subjects for IGCSE, O Level, AS & A Level, along with the duration, paper code, date, and AM/PM/EV session.
5. Save or Print the File
Once downloaded, you can either save the PDF on your device or print it for quick access. Many schools post this version on classroom notice boards, but keeping a personal copy is strongly recommended.
Bonus: Create a Custom View for Your Subjects
Cambridge now allows candidates to create a personalized timetable through their Direct platform (CIE Direct) or through partner educational portals. You can filter exams by:
Subject Name (e.g., Mathematics, Physics, Business Studies)
Qualification (IGCSE, O Level, AS Level, etc.)
Exam Session (AM/PM/EV)
This filtered list helps you visualize your own study sequence and avoid any potential timetable clashes.
Why It’s Important to Use the Final Timetable
The final timetable (Version 1, released October 2025) is the only confirmed and legally valid document for the May–June 2026 CAIE series.
Provisional timetables may differ slightly in:
Paper timings
Practical exam windows
Overlap management for multiple entries
Hence, always verify that your downloaded file mentions:
“Cambridge International June 2026 Final Timetable – Administrative Zone 4”
💡 Pro Tip:
Always double-check your subjects, paper codes, and sessions right after entries are submitted. If you find any overlapping papers, notify your exam officer to request a timetable deviation in advance.
Download Link (Official & Verified Source)
🔗 Download the Official CAIE O Level & IGCSE Datesheet – May–June 2026 (Zone 4)
This link leads directly to the Cambridge International official timetables page, where you can download the latest version safely and free of charge.
Next, let’s move on to something even more useful for students —
👉 How to Create Your Own Custom Exam Datesheet Online, using this official timetable to design a personalized schedule that matches your subjects and priorities.
Create Your Own Custom Exam Datesheet Online (CAIE 2026 – Zone 4)
The official CAIE O Level & IGCSE Datesheet May–June 2026 (Zone 4) provides all exam details, but every student’s subject combination is different. That’s why creating a personalized exam timetable is one of the smartest steps you can take while preparing for your Cambridge exams.
By designing your own datesheet, you’ll instantly know which exams are coming up, how many days you have between them, and where you can schedule focused revision time. Here’s a simple guide to creating your customized exam plan — whether you’re doing it manually, online, or through Cambridge’s own tools.
Option 1: Use the Official CAIE Direct Platform
Cambridge International offers a digital feature via its Cambridge Direct portal, allowing registered students and exam officers to generate a subject-specific timetable.
Here’s how to do it:
Log in using your Centre Number and Candidate ID (provided by your school).
Select the “Timetables” section.
Choose “June 2026 – Zone 4” from the dropdown menu.
Click “Generate My Timetable” to view only your subjects and paper codes.
The platform will automatically filter your exams and display them in date order, including paper duration, session type (AM/PM/EV), and any overlapping exams. You can then export this personalized timetable as a PDF or CSV file.
Option 2: Build a Manual Datesheet from the Official PDF
If you’re not using the Cambridge portal, you can still easily create a customized timetable using the official Zone 4 PDF you downloaded earlier.
Steps to do this manually:
Open the O Level & IGCSE May–June 2026 PDF.
Locate your subjects (for example: English Language 1123, Mathematics 4024, Physics 5054, etc.).
Note down:
The exact exam date
The session time (AM, PM, or EV)
The paper code (for example, 5054/12 or 4024/22)
The duration of each paper
Arrange them in a chronological list or table in a Word or Excel document.
Highlight subjects that are back-to-back or have less than one day’s gap — this helps prioritize your revision schedule.
This approach gives you a clear visual overview of your personal workload, helping you balance study time efficiently across all subjects.
Option 3: Use Online Timetable Creators or Apps
Several online tools now let you import your CAIE exam details and generate custom calendars:
🧠 ExamPlanner.io
📅 StudySmarter
🧾 Notion or Google Sheets templates
You can color-code your O Level and IGCSE subjects separately, set reminders, and even sync with Google Calendar for daily alerts.
Example:
Blue = Core Subjects (Maths, English, Science)
Yellow = Humanities (History, Islamiyat, Geography)
Green = Electives (Computer Science, Business, Literature)
Pro Tip: Plan Your Study Gaps Wisely
When you’ve built your custom datesheet, look for “study gaps” — days between two major exams.
Use those strategically for active revision, not new learning. Focus your energy on:
Past paper practice (available at https://www.cambridgeinternational.org/programmes-and-qualifications)
Reviewing mark schemes
Flashcards and quick quizzes for retention
Students who build a visual timeline of their exams tend to stay calmer and score higher because they can track progress with clarity.
Save and Print Your Timetable
Once finalized, export or print your personalized timetable and keep it:
📘 In your study notebook
📱 As a lock-screen or background image
📌 On your wall near your desk
This constant visibility helps you stay organized, confident, and stress-free as the May–June 2026 exams approach.
![Fundamental Concepts & States of Matter • Atom: The smallest particle of an element that can exist, made of a nucleus (protons and neutrons) and electrons orbiting it. • Element: A pure substance consisting of only one type of atom, which cannot be broken down into simpler substances by chemical means. • Compound: A substance formed when two or more different elements are chemically bonded together in a fixed ratio. • Mixture: A substance containing two or more elements or compounds not chemically bonded together. Can be separated by physical means. • Molecule: A group of two or more atoms held together by chemical bonds. • Proton: A subatomic particle found in the nucleus with a relative mass of 1 and a charge of +1. • Neutron: A subatomic particle found in the nucleus with a relative mass of 1 and no charge (0). • Electron: A subatomic particle orbiting the nucleus with a negligible relative mass and a charge of -1. • Atomic Number (Z): The number of protons in the nucleus of an atom. Defines the element. • Mass Number (A): The total number of protons and neutrons in the nucleus of an atom. • Isotopes: Atoms of the same element (same atomic number) but with different mass numbers due to a different number of neutrons. • Relative Atomic Mass ($A_r$): The weighted average mass of an atom of an element compared to $1/12$th the mass of a carbon-12 atom. • Relative Molecular Mass ($M_r$): The sum of the relative atomic masses of all atoms in one molecule of a compound. • Relative Formula Mass ($M_r$): The sum of the relative atomic masses of all atoms in the formula unit of an ionic compound. • Mole: The amount of substance that contains $6.02 \times 10^{23}$ particles (Avogadro's number). • Molar Mass: The mass of one mole of a substance, expressed in g/mol. Numerically equal to $A_r$ or $M_r$. • Empirical Formula: The simplest whole number ratio of atoms of each element in a compound. • Molecular Formula: The actual number of atoms of each element in a molecule. • Solid: Particles are closely packed in a fixed, regular arrangement, vibrate about fixed positions. Definite shape and volume. • Liquid: Particles are closely packed but randomly arranged, can slide past each other. Definite volume, no definite shape. • Gas: Particles are far apart and arranged randomly, move rapidly and randomly. No definite shape or volume. • Melting Point: The specific temperature at which a solid changes into a liquid at a given pressure. • Boiling Point: The specific temperature at which a liquid changes into a gas (vaporizes) at a given pressure. • Sublimation: The direct change of state from solid to gas without passing through the liquid phase (e.g., solid $\text{CO}_2$). • Diffusion: The net movement of particles from a region of higher concentration to a region of lower concentration, due to random motion. • Osmosis: The net movement of water molecules across a partially permeable membrane from a region of higher water potential to a region of lower water potential. 2. Structure & Bonding • Ionic Bond: The electrostatic force of attraction between oppositely charged ions, formed by the transfer of electrons from a metal to a non-metal. • Covalent Bond: A strong electrostatic force of attraction between a shared pair of electrons and the nuclei of the bonded atoms, typically between two non-metals. • Metallic Bond: The electrostatic force of attraction between positive metal ions and delocalised electrons. • Ion: An atom or group of atoms that has gained or lost electrons, resulting in a net electrical charge. • Cation: A positively charged ion (lost electrons). • Anion: A negatively charged ion (gained electrons). • Octet Rule: Atoms tend to gain, lose, or share electrons in order to achieve a full outer electron shell, typically with eight electrons. • Giant Ionic Lattice: A regular, repeating 3D arrangement of oppositely charged ions, held together by strong electrostatic forces. • Simple Molecular Structure: Molecules held together by strong covalent bonds, but with weak intermolecular forces between molecules. • Giant Covalent Structure (Macromolecular): A large structure where all atoms are held together by strong covalent bonds in a continuous network (e.g., diamond, silicon dioxide). • Allotropes: Different structural forms of the same element in the same physical state (e.g., diamond and graphite are allotropes of carbon). • Electronegativity: The power of an atom to attract the electron pair in a covalent bond to itself. • Polar Covalent Bond: A covalent bond in which electrons are shared unequally due to a difference in electronegativity between the bonded atoms. • Hydrogen Bond: A strong type of intermolecular force that occurs between molecules containing hydrogen bonded to a highly electronegative atom (N, O, F). • Van der Waals' forces: Weak intermolecular forces of attraction between all molecules, arising from temporary dipoles. 3. Stoichiometry & Chemical Calculations • Stoichiometry: The study of quantitative relationships between reactants and products in chemical reactions. • Limiting Reactant: The reactant that is completely consumed in a chemical reaction, determining the maximum amount of product that can be formed. • Excess Reactant: The reactant present in a greater amount than required to react with the limiting reactant. • Yield: The amount of product obtained from a chemical reaction. • Theoretical Yield: The maximum amount of product that can be formed from a given amount of reactants, calculated using stoichiometry. • Actual Yield: The amount of product actually obtained from a chemical reaction, usually less than the theoretical yield. • Percentage Yield: $($Actual Yield $/$ Theoretical Yield$) \times 100\%$. • Concentration: The amount of solute dissolved in a given volume of solvent or solution. Often expressed in mol/dm$^3$ (molarity) or g/dm$^3$. • Solute: The substance that dissolves in a solvent to form a solution. • Solvent: The substance in which a solute dissolves to form a solution. • Solution: A homogeneous mixture formed when a solute dissolves in a solvent. 4. Chemical Reactions & Energetics • Chemical Reaction: A process that involves rearrangement of the atomic structure of substances, resulting in the formation of new substances. • Reactants: The starting substances in a chemical reaction. • Products: The substances formed as a result of a chemical reaction. • Word Equation: An equation that uses the names of the reactants and products. • Symbol Equation: An equation that uses chemical symbols and formulae to represent reactants and products, and is balanced. • Balancing Equation: Ensuring the number of atoms of each element is the same on both sides of a chemical equation. • Redox Reaction: A reaction involving both reduction and oxidation. • Oxidation: Loss of electrons, gain of oxygen, or loss of hydrogen. Increase in oxidation state. • Reduction: Gain of electrons, loss of oxygen, or gain of hydrogen. Decrease in oxidation state. • Oxidising Agent: A substance that causes oxidation by accepting electrons (and is itself reduced). • Reducing Agent: A substance that causes reduction by donating electrons (and is itself oxidised). • Exothermic Reaction: A reaction that releases energy to the surroundings, usually as heat, causing the temperature of the surroundings to rise. $\Delta H$ is negative. • Endothermic Reaction: A reaction that absorbs energy from the surroundings, usually as heat, causing the temperature of the surroundings to fall. $\Delta H$ is positive. • Activation Energy ($E_a$): The minimum amount of energy required for reactants to collide effectively and initiate a chemical reaction. • Catalyst: A substance that increases the rate of a chemical reaction without being chemically changed itself, by providing an alternative reaction pathway with a lower activation energy. • Enthalpy Change ($\Delta H$): The heat energy change measured at constant pressure for a reaction. • Standard Enthalpy of Formation ($\Delta H_f^\circ$): The enthalpy change when one mole of a compound is formed from its constituent elements in their standard states under standard conditions. • Standard Enthalpy of Combustion ($\Delta H_c^\circ$): The enthalpy change when one mole of a substance is completely combusted in oxygen under standard conditions. • Hess's Law: The total enthalpy change for a reaction is independent of the route taken, provided the initial and final conditions are the same. 5. Rates of Reaction & Equilibrium • Rate of Reaction: The change in concentration of a reactant or product per unit time. • Collision Theory: For a reaction to occur, reactant particles must collide with sufficient energy (activation energy) and correct orientation. • Factors Affecting Rate: Concentration, pressure (for gases), surface area, temperature, and presence of a catalyst. • Reversible Reaction: A reaction where products can react to reform the original reactants, indicated by $\rightleftharpoons$. • Chemical Equilibrium: A state in a reversible reaction where the rate of the forward reaction is equal to the rate of the reverse reaction, and the concentrations of reactants and products remain constant. • Le Chatelier's Principle: If a change in conditions (temperature, pressure, concentration) is applied to a system at equilibrium, the system will shift in a direction that counteracts the change. 6. Acids, Bases & Salts • Acid: A substance that produces hydrogen ions ($H^+$) when dissolved in water (Arrhenius definition) or a proton donor (Brønsted-Lowry definition). • Base: A substance that produces hydroxide ions ($OH^-$) when dissolved in water (Arrhenius definition) or a proton acceptor (Brønsted-Lowry definition). • Alkali: A soluble base that dissolves in water to produce hydroxide ions ($OH^-$). • Salt: A compound formed when the hydrogen ion of an acid is replaced by a metal ion or an ammonium ion. • Neutralisation: The reaction between an acid and a base (or alkali) to form a salt and water. $H^+(aq) + OH^-(aq) \rightarrow H_2O(l)$. • pH: A measure of the acidity or alkalinity of a solution, defined as $-\log_{10}[H^+]$. Scale from 0 to 14. • Strong Acid: An acid that fully dissociates (ionizes) in water (e.g., HCl, $H_2SO_4$). • Weak Acid: An acid that partially dissociates (ionizes) in water (e.g., $CH_3COOH$). • Strong Base: A base that fully dissociates in water (e.g., NaOH, KOH). • Weak Base: A base that partially dissociates in water (e.g., $NH_3$). • Amphoteric: A substance that can act as both an acid and a base (e.g., aluminium oxide, water). • Titration: A quantitative chemical analysis method used to determine the unknown concentration of a reactant using a known concentration of another reactant. • Indicator: A substance that changes colour over a specific pH range, used to detect the endpoint of a titration. 7. Electrochemistry • Electrolysis: The decomposition of an ionic compound using electrical energy. Requires molten or aqueous electrolyte. • Electrolyte: An ionic compound (molten or dissolved in a solvent) that conducts electricity due to the movement of ions. • Electrodes: Conductors (usually metal or graphite) through which electricity enters and leaves the electrolyte. • Anode: The positive electrode, where oxidation occurs (anions are attracted). • Cathode: The negative electrode, where reduction occurs (cations are attracted). • Faraday's Laws of Electrolysis: Relate the amount of substance produced at an electrode to the quantity of electricity passed through the electrolyte. • Galvanic (Voltaic) Cell: An electrochemical cell that generates electrical energy from spontaneous redox reactions. • Standard Electrode Potential ($E^\circ$): The potential difference of a half-cell compared to a standard hydrogen electrode under standard conditions (1 M concentration, 1 atm pressure for gases, 298 K). • Electrochemical Series: A list of elements arranged in order of their standard electrode potentials, indicating their relative reactivity as oxidising or reducing agents. 8. The Periodic Table • Periodic Table: An arrangement of elements in order of increasing atomic number, showing periodic trends in properties. • Group: A vertical column in the periodic table, containing elements with the same number of valence electrons and similar chemical properties. • Period: A horizontal row in the periodic table, containing elements with the same number of electron shells. • Valence Electrons: Electrons in the outermost shell of an atom, involved in chemical bonding. • Alkali Metals (Group 1): Highly reactive metals, readily lose one electron to form $+1$ ions. React vigorously with water. • Alkaline Earth Metals (Group 2): Reactive metals, readily lose two electrons to form $+2$ ions. • Halogens (Group 17/7): Highly reactive non-metals, readily gain one electron to form $-1$ ions. Exist as diatomic molecules. • Noble Gases (Group 18/0): Unreactive elements with a full outer electron shell, existing as monatomic gases. • Transition Metals: Elements in the d-block of the periodic table, characterised by variable oxidation states, coloured compounds, and catalytic activity. • Metallic Character: Tendency of an element to lose electrons and form positive ions. Increases down a group, decreases across a period. • Non-metallic Character: Tendency of an element to gain electrons and form negative ions. Decreases down a group, increases across a period. • Ionisation Energy: The energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous $1+$ ions. • Electron Affinity: The energy change when one mole of electrons is added to one mole of gaseous atoms to form one mole of gaseous $1-$ ions. 9. Organic Chemistry • Organic Chemistry: The study of carbon compounds, excluding carbonates, carbides, and oxides of carbon. • Hydrocarbon: A compound containing only carbon and hydrogen atoms. • Saturated Hydrocarbon: A hydrocarbon containing only single carbon-carbon bonds (e.g., alkanes). • Unsaturated Hydrocarbon: A hydrocarbon containing one or more carbon-carbon double or triple bonds (e.g., alkenes, alkynes). • Homologous Series: A series of organic compounds with the same general formula, similar chemical properties, and showing a gradual change in physical properties. • Functional Group: A specific group of atoms within a molecule that is responsible for the characteristic chemical reactions of that molecule. • Alkane: Saturated hydrocarbons with the general formula $C_nH_{2n+2}$. Contain only single bonds. • Alkene: Unsaturated hydrocarbons with the general formula $C_nH_{2n}$. Contain at least one carbon-carbon double bond. • Alkyne: Unsaturated hydrocarbons with the general formula $C_nH_{2n-2}$. Contain at least one carbon-carbon triple bond. • Alcohol: Organic compounds containing the hydroxyl functional group ($-OH$). General formula $C_nH_{2n+1}OH$. • Carboxylic Acid: Organic compounds containing the carboxyl functional group ($-COOH$). • Ester: Organic compounds formed from the reaction of a carboxylic acid and an alcohol, containing the ester linkage ($-COO-$). • Isomers: Compounds with the same molecular formula but different structural formulae. • Structural Isomers: Isomers that differ in the arrangement of their atoms or bonds. • Addition Reaction: A reaction where an unsaturated molecule adds across a double or triple bond, forming a single product. • Substitution Reaction: A reaction where an atom or group of atoms in a molecule is replaced by another atom or group of atoms. • Polymerisation: The process of joining many small monomer molecules together to form a large polymer molecule. • Monomer: A small molecule that can be joined together to form a polymer. • Polymer: A large molecule (macromolecule) formed from many repeating monomer units. • Addition Polymerisation: Polymerisation where monomers add to one another in such a way that the polymer contains all the atoms of the monomer. Usually involves unsaturated monomers. • Condensation Polymerisation: Polymerisation where monomers join together with the elimination of a small molecule (e.g., water). • Cracking: The process of breaking down long-chain hydrocarbons into shorter, more useful hydrocarbons using heat and/or a catalyst. • Fermentation: The anaerobic respiration of yeast, converting glucose into ethanol and carbon dioxide. 10. Analytical Chemistry • Qualitative Analysis: The identification of the components of a sample. • Quantitative Analysis: The determination of the amount or concentration of a component in a sample. • Chromatography: A separation technique based on differential partitioning between a stationary phase and a mobile phase. • Retention Factor ($R_f$): In paper/thin-layer chromatography, the ratio of the distance travelled by the spot to the distance travelled by the solvent front. • Spectroscopy: The study of the interaction of electromagnetic radiation with matter. • Infrared (IR) Spectroscopy: Used to identify functional groups in organic molecules based on their absorption of IR radiation. • Mass Spectrometry: Used to determine the relative molecular mass of a compound and its fragmentation pattern to deduce structure. • Flame Test: A qualitative test for the presence of certain metal ions, which produce characteristic colours when heated in a flame.](data:image/svg+xml;base64,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)