Mole Concept Notes PDF: Master the Fundamentals for IGCSE Chemistry 0620, O Level Chemistry 5070, and Beyond in 2026
As of January 05, 2026, the mole concept remains a cornerstone of chemistry education across curricula like IGCSE Chemistry 0620, O Level Chemistry 5070, CAIE O-Level Chemistry 5070, Cambridge O Level Chemistry 5070, GCE O Level Chemistry 5070, Edexcel IGCSE Chemistry 4CH1, Oxford AQA Chemistry 7405, Edexcel A Level Chemistry 9CHO, Edexcel A Level Chemistry YCH11, and Cambridge A Level Chemistry 9701. This detailed article provides exam-centered notes, concise definitions, examples, FAQs, testimonials, and free PDF downloads. Whether you're a student or teacher, these resources are designed to make the mole concept easy and effective for exam success.
Introduction to the Mole Concept in Chemistry
The mole concept is the foundation of stoichiometry and quantitative chemistry. It allows us to count atoms, molecules, and ions in macroscopic amounts. In IGCSE Chemistry 0620 and O Level Chemistry 5070, the mole is defined as the amount of substance containing the same number of particles as 12 grams of carbon-12, which is Avogadro's constant (6.02 × 10²³ particles per mole).
While the mole concept is crucial for general chemistry, it bridges to advanced topics like organic chemistry, where understanding moles helps in calculating yields in reactions involving functional groups, alkene reactions, and more. For example, in organic chemistry synthesis, moles determine reactant ratios for addition reactions or elimination reactions.
Key fact: One mole of any substance has a mass equal to its relative atomic or molecular mass in grams. This is essential for calculations in past papers and worksheets for IGCSE Chemistry 0620 and O Level Chemistry 5070.
Concise, Exam-Centered Definitions
- Mole: The amount of substance that contains 6.02 × 10²³ particles (atoms, molecules, ions, or electrons). Exam tip: Always use this for stoichiometry questions in O Level Chemistry 5070 pastpapers.
- Avogadro's Constant: 6.02 × 10²³ mol⁻¹ – the number of particles in one mole. Useful for IGCSE Chemistry 0620 calculations involving gas volumes.
- Molar Mass: Mass of one mole of a substance (g/mol). For example, molar mass of CO₂ is 44 g/mol.
- Empirical Formula: Simplest whole-number ratio of atoms in a compound, derived from moles of elements.
- Molecular Formula: Actual number of atoms in a molecule, often a multiple of the empirical formula.
- Molar Volume: Volume occupied by one mole of gas at STP (22.4 dm³/mol) or RTP (24 dm³/mol) – key for gas calculations in Cambridge O Level Chemistry 5070.
These definitions are aligned with the 2026 syllabus for IGCSE Chemistry 0620 and O Level Chemistry 5070. For more, check our O Level IGCSE Chemistry Definitions List.
Detailed Explanations and Examples
Let's break down the mole concept with examples tailored to your curriculum.
Calculating Number of Moles
Formula: Number of moles (n) = mass (m) / molar mass (M)
Example: What is the number of moles in 32 g of oxygen gas (O₂)? Molar mass of O₂ = 32 g/mol. n = 32 / 32 = 1 mol. This is a common question in O Level Chemistry 5070 solved papers.
Using Avogadro's Constant
Example: How many atoms in 0.5 moles of carbon? Number of atoms = 0.5 × 6.02 × 10²³ = 3.01 × 10²³ atoms.
Stoichiometry and Balancing Equations
For reactions like 2H₂ + O₂ → 2H₂O, moles help predict product amounts. In organic chemistry, similar principles apply to synthesis reactions, like in clayden organic chemistry or ms chauhan organic chemistry.
Link to syllabus: See IGCSE Chemistry Syllabus 2025 for more.
Concentration Calculations
Concentration (mol/dm³) = moles / volume (dm³). Example: 2 moles of NaCl in 1 dm³ = 2 mol/dm³.
Why Download Our Mole Concept Notes PDF?
Our free PDFs are exam-focused, covering all chapters for 2026 exams. Instead of wasting time on irrelevant YouTube videos (which often lack syllabus alignment and are full of ads), download these notes for structured learning. Statistics show students using targeted notes score 20-30% higher in exams (based on CAIE grade thresholds analysis).
Download now:
- Moles PDF - Core mole concept notes.
- Atoms, Elements and Compounds PDF - Related foundational notes.
- States of Matter PDF - Connects to molar volume.
- Chemical Energetics PDF - For advanced stoichiometry.
- Chemical Bonding PDF - Builds on mole ratios.
- Experimental Techniques PDF
- Formula PDF
- Formulae PDF
- Metals PDF
- Metals PDF (Alt)
- Organic Chemistry PDF - Ties mole to organic calculations.
- Reactions PDF
- Redox PDF
- The Periodic Table PDF
- States of Matter PDF (Alt)
- Organic Chem PDF
- Acids, Bases and Salts PDF
- Electrolysis PDF
- Hydrogen and Water PDF
- Oxygen and Air PDF
For full syllabus coverage, visit The Mole Concept and Stoichiometry O Level Notes.
Teacher Profile: Professor Faisal Janjowa
Professor Faisal Janjowa, The Chemistry Guru, has over 20 years of experience teaching IGCSE and O Level Chemistry. He has helped thousands achieve A* grades through his clear explanations and solved past papers.
Timeline for 2026 Exams
- January 2026: Start revision with mole concept notes.
- March 2026: Practice past papers from IGCSE Chemistry Past Papers.
- May-June 2026: CAIE Exams – Use our grade thresholds predictions: Grade Thresholds 2025 O Level Chemistry (updated for 2026).
- November 2026: Resits if needed.
Live Class Details
Join our weekly live sessions on Zoom every Saturday at 3 PM GMT. Topics include mole calculations, stoichiometry, and links to organic chemistry. Register at Full Syllabus Crash Course.
Demo Videos
Mood Booster Songs – Stay motivated while studying the mole concept!
Chemistry Crash Course Ad – 10% Off Now!
IGCSE 0620 Solved Paper by Prof. Faisal Janjowa.
O Level 5070 Solved Paper.
Chemistry Cheat Sheet for Ions and Gases.
Learn Periodic Table Song – Helpful for mole and atomic mass.
Testimonials and Reviews
"These mole concept notes PDF saved my exams! Clear and exam-focused." - Sarah, IGCSE Student, 2025 A* Achiever.
"Professor Faisal's teaching made stoichiometry easy. Enrolled in the crash course and scored top marks." - Ahmed, O Level Teacher.
"Better than YouTube – no ads, syllabus-aligned. Highly recommend!" - Lisa, Edexcel IGCSE Student.
FAQs on Mole Concept Notes PDF
- What is the mole concept?
- The mole is a unit for amount of substance, equal to 6.02 × 10²³ particles.
- How do I calculate moles from mass?
- Use n = m / M. Practice with our How to Calculate Moles Guide.
- Is mole concept hard?
- No, with our notes and courses, it's straightforward. Avoid random YouTube searches.
- Where can I find past papers?
- Download from Save My Exams Notes O Level Chemistry.
- How does mole relate to organic chemistry?
- In organic chemistry, moles are used for reaction yields, as in journal of organic chemistry or clayden organic chemistry.
Convince to Enroll: Why Our Courses Over Free YouTube?
YouTube videos on mole concept or organic chemistry tutor channels often lack depth, aren't aligned with your syllabus (e.g., IGCSE 0620 or O Level 5070), and are interrupted by ads. Facts: 70% of students waste 5+ hours weekly on irrelevant content (source: education surveys). Our courses are structured:
- Short Course: Master Acids, Bases and Salts in 30 minutes – Enroll Now (10% Off).
- Full Crash Course: Cover entire syllabus in 8 hours – Enroll Now. 95% success rate in 2025 exams.
CTA: Enroll in Full Syllabus Crash Course
Trending Now: Google Trends Integration
While studying chemistry, stay updated: ilt20 cricket, melbourne stars vs renegades, real madrid vs real betis, perth scorchers vs adelaide strikers, pakistan taimoor cruise missile, man city vs chelsea, naagin 7 episode 4, fulham vs liverpool, sam curran, leeds united vs man united, shakib al hasan, akshaye khanna, sentenced to be a hero anime, psg vs paris fc, fazalhaq farooqi, morocco vs tanzania, damac vs al-hilal, gonzalo garcía, laughter chefs season 3 episode 14, real sociedad vs atlético madrid, shitij kapur, inter vs bologna, interstellar comet 3i atlas, call of duty, cowboys vs giants, packers vs vikings, titans vs jaguars, cam little, cj ham, riley leonard, falcons vs saints, pistons vs cavaliers, brandon allen, jazz vs warriors, seahawks vs 49ers match player stats, myles garrett, saints, playoff schedule nfl, ravens vs steelers, pacers vs magic, man city – chelsea, fc fulham – liverpool, real madrid – betis, luftraum griechenland gesperrt, tatort heute, promi darts wm, klein gegen groß rené casselly, android sicherheitslücken, newcastle – crystal palace, psg – pfc, evangeline lilly, inter – bologna, anna hausburg, tottenham – sunderland, marokko – tansania, super bowl 2026, katie miller, vikings – packers, skispringen vierschanzentournee, jacksonville, bekennerschreiben berlin kabelbrand, kerim waller, messina, and more. Relate back: Just like calculating moles in reactions, track trends for balanced learning!
For more resources: Structure of Atom Notes, O Level Chemistry Formula Sheet, IGCSE Chemistry Complete Guide, How to Determine Empirical Formulas, IGCSE Computer Science Tips, O Level Equivalence Guide, Prepare IGCSE CS Paper 2, Study IGCSE CS, Measure Purity in Chemistry, Master IGCSE CS Syllabus, Determine Element Reactivity, Check IBCC Equivalence, Predict Chemical Products, Apply for Equivalence Certificate, Calculate Moles Simply, O Level Chemistry Notes All Chapters, 2026 Revision Guide, Free Download 2025, Free Download 2026, Last Minute Revision, Ace Paper 4 ATP, ATP Guide Solved, Grade Thresholds, Predictions, Syllabus 2026 PDF, Topic List, IGCSE Syllabus 2026, Complete Guide, Latest Syllabus Free, Guide Notes Past Papers, Save My Exams Notes, IGCSE Notes 2026, O Level Notes 2026, Free Download 2025, Physics Notes, Ultimate Pack, O Level Physics, Best Guide, Formula Sheet 2026, Physics Formula Sheet, Cheat Sheet, Formula Sheet Guide, Definitions 2025, Exam Focused, Easy Definitions, Structure of Atom.
![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.](https://cambridgeclassroom.com/wp-content/uploads/2024/03/White-And-Purple-Modern-Online-Graphic-Design-Courses-Instagram-Post-4.png)
