Periodic Table പീരിയോഡിക് ടേബിൾ
The chapter opens in a classroom. Four students are building a periodic table (പീരിയോഡിക് ടേബിൾ) out of cardboard boxes, one box for each element, with two separate rows along the bottom. Why are the elements arranged this way, and what can a box's position tell you? In this chapter you will follow the story. Mendeleev arranged the elements by atomic mass in 1869, and Moseley later showed that atomic number is the true order (the modern periodic law). You will learn to read the modern table of 118 elements: periods and groups, families such as the alkali metals, halogens and noble gases, the transition elements, and the lanthanoids and actinoids. You will find any element's group and period from its electron configuration, and see why atoms get bigger down a group and smaller across a period. This self-study guide starts from the basics: elements, symbols and the shells of an atom. It explains every idea step by step with animations and virtual labs, answers every textbook question, and ends with a revision sheet and a model test.
The chapter in one picture
The cards go in order of atomic number (അറ്റോമിക നമ്പർ): 1, 2, 3 … 118. A new row, or period (പീരിയഡുകൾ), starts each time a new shell begins to fill. Elements in the same column, or group (ഗ്രൂപ്പുകൾ), have the same number of outermost electrons (ബാഹ്യതമ ഇലക്ട്രോണുകൾ), so they behave alike. Colours: blue = metals, green = non-metals, amber = metalloids. Lanthanum to lutetium (57–71) and actinium to lawrencium (89–103) sit in the two rows below the table.
How to use this guide
🎬 Watch the animations
Electrons fill the shells, a period fills from 1 to 8 outer electrons, and atoms shrink across a period, one step at a time. Press Next ▶ or ▶▶ Auto play. Animations pause by themselves when you scroll away; click a lab to start its clock again.
🧪 Use the virtual labs
Your textbook suggests the free program Kalzium. This guide has its own interactive periodic table instead: click any element to see its configuration, shells, group and period. Sort Mendeleev's cards, find groups and periods, and compare atom sizes.
✍️ Try before you see
Every question has a 💡 hint first and a ✅ final answer after. Work it out in your notebook, then check. The “Check yourself” quizzes at the end of each page tell you at once whether you are right.
📖 Textbook words
Purple മലയാളം words are the exact terms used in your textbook (pages 23–42), so you can match this guide with your book and write answers in either language.
🔇 Quiet and offline
The pages make no sound, need no internet. Optional "Explore online" boxes link to checked websites (no videos); they open only if you click them. Every page is a single file, so the whole guide works on a computer or phone with no connection.
Learning path
Follow the pages in order. If you already know element symbols, metals and non-metals, and how to write a configuration such as 2, 8, 8, 1, you can skim pages 1–2. Still try their quizzes, because the chapter uses these ideas on every page.
Scientists in this chapter
Four scientists stand out in this chapter's story, from the first periodic law to the newest elements. Here they are as name cards (no photos), in order.
Also in the story: Johann Döbereiner (groups of three similar elements, “triads”, 1829) and John Newlands (“law of octaves”, 1865), whose early attempts you will meet on page 3.
Quick glossary (Malayalam ↔ English)
| Textbook term | English | Meaning |
|---|---|---|
| പീരിയോഡിക് ടേബിൾ | Periodic table | The chart that arranges all the elements so that similar ones fall in the same column |
| പീരിയോഡിക് നിയമം | Periodic law | Mendeleev (1869): the properties of elements are periodic functions of their atomic masses |
| ആധുനിക പീരിയോഡിക് നിയമം | Modern periodic law | The chemical and physical properties of elements are periodic functions of their atomic numbers |
| ആധുനിക പീരിയോഡിക് ടേബിൾ | Modern periodic table | The table of 118 elements in increasing order of atomic number: 7 periods and 18 groups |
| മെൻഡലീഫ് (ദിമിത്രി ഇവാനോവിച്ച്) | Dmitri Ivanovich Mendeleev | Russian chemist who made the first periodic table (1869), leaving gaps for undiscovered elements |
| ഹെൻറി മോസ്‌ലി | Henry Moseley (1887–1915) | British physicist whose X-ray experiments showed that atomic number is the true basis of order |
| എക്സ്റേ ഡിഫ്രാക്ഷൻ പരീക്ഷണങ്ങൾ | X-ray diffraction experiments | Moseley's experiments with the X-rays given out by different elements |
| അറ്റോമിക മാസ് · അറ്റോമിക നമ്പർ | Atomic mass · atomic number | The mass of an atom (in u) · the number of protons in the nucleus (Z) |
| ആരോഹണക്രമം | Ascending (increasing) order | From smallest to largest, e.g. 1, 2, 3 … |
| മേന്മകൾ · പരിമിതികൾ | Merits · limitations | The good points of a table · what it could not explain |
| ആവർത്തനഫലങ്ങൾ | Periodic functions | Properties that repeat at regular intervals as the atomic number increases |
| രാസഗുണങ്ങൾ · ഭൗതികഗുണങ്ങൾ | Chemical properties · physical properties | How an element reacts · how it looks and behaves without changing (state, shine, melting point …) |
| പീരിയഡുകൾ (വിലങ്ങനെയുള്ള നിരകൾ) | Periods (horizontal rows) | The 7 rows of the table; period number = number of shells |
| ഗ്രൂപ്പുകൾ (കുത്തനെയുള്ള കോളങ്ങൾ) | Groups (vertical columns) | The 18 columns; elements in a group have similar properties |
| മൂലക കുടുംബങ്ങൾ | Families of elements | Groups with a common name because of their common features |
| ആൽക്കലി ലോഹങ്ങൾ | Alkali metals | Group 1 (except hydrogen): lithium, sodium, potassium … |
| ആൽക്കലൈൻ എർത്ത് ലോഹങ്ങൾ | Alkaline earth metals | Group 2: beryllium, magnesium, calcium … |
| സംക്രമണ മൂലകങ്ങൾ | Transition elements | Groups 3–12, all metals, starting from period 4 |
| ബോറോൺ / കാർബൺ / നൈട്രജൻ / ഓക്സിജൻ കുടുംബം | Boron / carbon / nitrogen / oxygen family | Groups 13, 14, 15 and 16 |
| ഹാലൊജനുകൾ | Halogens | Group 17: fluorine, chlorine, bromine, iodine … |
| ഉൽകൃഷ്ട വാതകങ്ങൾ | Noble gases | Group 18: helium, neon, argon … – stable, they generally do not react |
| പ്രധാനഗ്രൂപ്പ് മൂലകങ്ങൾ | Main group elements | The elements of groups 1, 2 and 13–18 |
| ലോഹങ്ങൾ · അലോഹങ്ങൾ · ഉപലോഹങ്ങൾ | Metals · non-metals · metalloids | Shiny, malleable conductors · usually dull, brittle non-conductors · elements with both natures |
| ഖരം · ദ്രാവകം · വാതകം | Solid · liquid · gas | The three physical states, coloured differently in the textbook's table |
| ബാഹ്യതമ ഷെൽ · ബാഹ്യതമ ഇലക്ട്രോണുകൾ | Outermost shell · outermost electrons | The last shell that has electrons · the electrons in it |
| ബാഹ്യതമ ഷെല്ലിന് തൊട്ടുള്ളിലുള്ള ഷെൽ | Penultimate shell | The shell just inside the outermost shell, where transition elements fill their electrons |
| ഇലക്ട്രോൺ വിന്യാസം · ഇലക്ട്രോൺ പൂരണം | Electron configuration · filling of electrons | The arrangement of electrons in shells, e.g. 2, 8, 1 · the order in which shells are filled |
| ഷെല്ലുകളുടെ എണ്ണം | Number of shells | How many shells an atom has = its period number |
| സ്ഥിരത | Stability | An atom with 8 outermost electrons (helium: 2) is stable |
| രാസപ്രവർത്തനങ്ങൾ | Chemical reactions | Changes in which substances react to form new substances; the outermost electrons take part |
| ലോഹസ്വഭാവം · സംക്രമണം | Metallic character · transition | How metal-like an element is · a gradual change from one kind to another |
| നിറമുള്ള സംയുക്തങ്ങൾ | Coloured compounds | Most compounds of transition elements are coloured, e.g. blue copper sulphate |
| ലാൻഥനോയ്ഡുകൾ · ആക്റ്റിനോയ്ഡുകൾ | Lanthanoids · actinoids | La (57) to Lu (71) · Ac (89) to Lr (103): the two rows below the table |
| അന്തഃസംക്രമണ മൂലകങ്ങൾ · റെയർ എർത്ത്സ് | Inner transition elements · rare earths | Lanthanoids and actinoids together · another name for the lanthanoids |
| മനുഷ്യനിർമിതം · കൃത്രിമ മൂലകങ്ങൾ | Man-made · artificial elements | Elements made in laboratories: technetium, promethium and those after uranium (92) |
| ട്രാൻസ്‌യുറേനിയം മൂലകങ്ങൾ · റേഡിയോ ആക്ടീവ് സ്വഭാവം | Transuranium elements · radioactive nature | Elements after uranium · they are unstable and give out radiation |
| ക്രമാവർത്തന പ്രവണത | Periodic trend | A gradual change of a property along a period or down a group |
| ആറ്റത്തിന്റെ വലിപ്പം · അറ്റോമിക ആരം | Size of the atom · atomic radius | The distance from the centre of the nucleus to the outermost shell |
| ന്യൂക്ലിയർ ചാർജ് · ആകർഷണബലം | Nuclear charge · force of attraction | The positive charge of the nucleus (number of protons) · its pull on the electrons |
| സ്ക്രീനിംഗ് പ്രഭാവം (ഷീൽഡിംഗ് പ്രഭാവം) | Screening (shielding) effect | Inner electrons reduce the pull of the nucleus on the outer electrons |
| അയോണീകരണ ഊർജം · ഇലക്ട്രോനെഗറ്റിവിറ്റി | Ionisation energy · electronegativity | Two more periodic trends, studied in the next unit |
| പുതിയതായി കണ്ടെത്തിയ മൂലകങ്ങൾ | Newly discovered elements | Nihonium (113), moscovium (115), tennessine (117) and oganesson (118), named in 2016 |
| സൂചനകൾ | Key (legend) | The box that explains the colours of a table: gases, liquids, artificial elements |
🌐 Explore online (optional)
Want to go further? Each teaching page ends with a few checked websites and simulations (no videos), and page 12 has the full resources hub. They need the internet; the guide itself works offline.
- 📄 Periodic table Wikipedia
Everything about the table: history, layout and trends. - 🧪 Build an Atom (PhET simulation) PhET, University of Colorado Boulder
Build atoms and watch where each one sits in the periodic table.
Made for self-learning. Works offline – every page is a single file; only the optional "Explore online" links need the internet. Study material prepared by Claude for Madhu's family study folder, October 2026.