Atomic Number And Mass Number
Chapter Name : Structure Of The Atom |
Sub Topic Code : 102_09_04_05_02 |
Topic Name : Atomic Number And Mass Number |
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Sub Topic Name : Mass Number |
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Introduction
• Mass of an atom is mainly due to the mass of the protons and neutrons • Electrons have very low mass. • Protons and neutrons together are called nucleons. • The mass number is the sum of the total number of protons and neutrons present in the nucleus of an atom. • Mass of an atom = mass number denoted by A.
Pre-Requisites:
Daltons atomic theory, molecules, electrons
Activity:
Atoms are the smallest units of any substance.
Real Life Question:
What does an atom look like?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Atom | Smallest unit of a compound. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| A racing track | Centre of the track is the nucleus having protons and neutrons, the running tracks are the orbits and the racers are the electrons. |
Real life uses :
Atoms make up all substances.
Places to visit :
Laboratory.
Practical examples around us
| Examples | Explainations |
|---|---|
| A racing track | Centre of the track is the nucleus having protons and neutrons, the running tracks are the orbits and the racers are the electrons. |
What you learn in Theory:
• Mass of an atom is mainly due to the mass of the protons and neutrons. • Electrons have very low mass. • Protons and neutrons together are called nucleons. • The mass number is the sum of the total number of protons and neutrons present in the nucleus of an atom. Mass of an atom = mass number denoted by A.
What you learn in Practice:
Mass of an atom is due to the mass of protons and neutrons.