On the basis of Dalton’s Atomic Theory
The smallest particles of matter are called Atoms.
Characteristics of atoms:
- Atom is the smallest particle of matter.
- All elements are made of tiny particles called atom.
- Atoms are very small in size and cannot be seen through naked eyes.
- Atom does not exist in free-state in nature. But atom takes part in a chemical reaction.
- The properties of a matter depend upon the characteristics of atoms.
- Atoms are the building block of an element similar to a brick which combine together to make a building.
- The size of atoms is indicated by its radius.
- In ancient time atoms was considered indivisible.
1: (a) Fe, 2: (c) Gold, 3: (d) Silver, 4: (c) Na, 5: (b) K, 6: (a) Pb, 7: (b) Sn, 8: (c) Mercury, 9: (d) Natrium, 10: (a) Kalium
Symbols of Atoms of Elements
For the sake of convenience, elements are represented by unique symbols. For example: Hydrogen is represented by ‘H’.
Oxygen is represented ‘O’.
Nitrogen is represented by ‘N’.
Iron is represented by ‘Fe’.
Names and Symbols of some elements
Symbols of many elements are taken from their English name, while symbols of many others are taken from their Greek or Latin names.
Symbols of some element which are derived from their Latin name
|English name||Symbol||Latin name|
Several elements are named after the place where they discovered. Example: Copper was discovered in Cyprus. Thus, it got its name similar to Cyprus.
Some elements are named after their colour. Example: Gold means yellow.