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224 pages, Paperback
First published July 1, 2007
1. An element is a pure substance which is made up of only one kind of atoms.
2. An atom is the smallest particle of an element which may or may not have independent existence.
3. Molecule is the smallest paricle of a substance which is capable of independent existence under ordinary conditions and show all the properties of that substance.
4. The combining capacity of an element is known as its valency.
5. Ion is a charged particle having negative or positive charge.
6. The mass number is defined as the sum of the number of protons and neutrons in an atom of the element.
7. Isotopes are the atoms of same element which have same atomic number but different mass number.
8. Isobars are the atoms of different elements having same mass number but different atomic number.