Structure Of An Atom
Chapter Name : Atoms And Molecules |
Sub Topic Code : 102_09_03_02_02 |
Topic Name : Structure Of An Atom |
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Sub Topic Name : Atomic Mass |
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Introduction
According to Dalton each element has an atomic mass. Relative atomic masses were determined using the laws of chemical combinations and the compounds formed. Atomic mass unit is used as a standard. It represents the mass of 1/12 the mass of one atom of carbon-12.
Pre-Requisites:
Atom, matter, element
Activity:
Each compound is represented by symbols of the atoms of each element present in the compound and each atom has its specific atomic mass.
Real Life Question:
How to calculate the mass of a compound?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Representation | Elements have their own unique representation. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Periodic table | Use a periodic table to see the symbols and atomic mass units of different atoms. |
Real life uses :
Atomic mass helps to calculate the mass of compounds.
Places to visit :
Chemistry lab.
Practical examples around us
| Examples | Explainations |
|---|---|
| Water is denoted by the formula H2O | Water is denoted by the symbols for hydrogen and oxygen. Its atomic mass would be the sum of the two atoms of hydrogen and one atom of oxygen. |
What you learn in Theory:
All matter around us is made up of atoms There is a large variety of matter around us therefore each atom should have a unique representation. Dalton used symbols for elements. IUPAC approves names of elements. The representation of atoms helps us to differentiate one element from another.
What you learn in Practice:
To determine the mass of a compound or element.