Skip to main content
Chapter 5 of 9
Revision Notes

The Periodic Table

ICSE · Class 9 · Chemistry

Quick revision notes for The Periodic Table — ICSE Class 9 Chemistry. Key concepts, formulas, and definitions for last-minute revision.

44 questions25 flashcards5 concepts

Interactive on Super Tutor

Studying The Periodic Table? Get the full interactive chapter.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for revision notes and more.

1,000+ Class 9 students started this chapter today

An infographic explaining the historical need and benefits of classifying elements, such as ease of study, prediction of properties, and systematic organization.
Super Tutor

This is just one of 15+ visuals inside Super Tutor's The Periodic Table chapter

Explore the full set

Key Topics to Revise

1

Historical Development of Periodic Classification

  • Classification became necessary as more elements were discovered in the 18th and 19th centuries
  • Early attempts based on density, malleability, and metallic/non-metallic nature were unsuccessful
  • Dobereiner's Triads (1817): Elements grouped in sets of three with similar properties
2

Modern Periodic Law and Table Structure

  • Henry Moseley (1913) discovered atomic number as the fundamental property
  • Modern Periodic Law: Properties are periodic functions of atomic numbers
  • Atomic number = number of protons in nucleus = number of electrons in neutral atom
3

Periodic Trends and Properties

  • Down a group: atomic size increases, metallic character increases, reactivity of metals increases
  • Across a period: atomic size decreases, metallic character decreases, valence electrons increase
  • Valency with hydrogen: increases 1→4 then decreases 4→1 across period
4

Group 1: Alkali Metals

  • Elements: Li, Na, K, Rb, Cs, Fr
  • Electronic configuration: ns¹ (one valence electron)
  • Highly reactive metals, reactivity increases down the group

Get complete notes with diagrams and examples

Full Notes

Key Concepts

JWhen elements are arranged in increasingPhysical and chemical properties of elementsPhysical and chemical properties of elementsThe number of unit positive charges

Frequently Asked Questions

What are the important topics in The Periodic Table for ICSE Class 9 Chemistry?
The Periodic Table covers several key topics that are frequently asked in ICSE Class 9 board exams. Focus on the core concepts listed on this page and practise related questions to build confidence.
How to score full marks in The Periodic Table — ICSE Class 9 Chemistry?
Start by understanding all key concepts. Practise previous year questions from this chapter. Revise formulas and definitions regularly. Use flashcards for quick revision before the exam.

Sources & Official References

Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.

For serious students

Get the full The Periodic Table chapter — for free.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan for ICSE Class 9 Chemistry.