Page 69 - ICSE Chemistry 8

4 Atomic Structure

Learning Outcomes Key Concepts
Students will be able to
• Ancient View on Atomic
• describe that an atom consists of electrons, protons and neutrons.
Structure
• defi ne atomic number and mass number.
• Dalton’s Atomic Theory
• discuss valency of elements and radicals with respect to the number of • Subatomic Particles and
hydrogen atoms combining with one atom of the element.
Their Discovery
• Modern Concept of an
Atom
• Structural Stability of an
Atom
• Atomic Number
• Mass Number
• Relative Atomic Mass
• Isotopes
• Electronic Confi guration
• Valency
• Chemical Bond

Warm Up Activity

Based on your previous knowledge, answer the following ques ons.

• What is an atom?

___________________________________________________________

• What is an anion?

___________________________________________________________

• What is a ca on?

___________________________________________________________

Everything around us is made up of ma er. Atoms are the building blocks of ma er and cannot be
chemically subdivided by ordinary means. Atoms of diff erent elements combine to form diff erent types
of ma er. They take part in chemical reac ons and exhibit the proper es of that element. The word atom
is derived from the Greek word atomos which means indivisible.

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