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Electrons,protons and neutrons are the subatomic particles
Protons have positive charge and are present in the nucleus
The name of an element depends on the number of protons
Neutrons does not have any charge and are present in the nucleus
Nucleon number is the total number of protons and neutrons in the nucleus
Electrons revolve around the nucleus and have negative charge
An atom can have maximum 2 electrons in the 1st shell,8 in the second shell,8 in the 3rd shell
The arrangement of electrons in the different shells is called electronic configuration
An atom can lose or gain electrons to have inert gas configuration.
Inert gases are present in group 8 of the periodic table . They are monoatomic unreactive gases
When an atom has more protons than electrons,it will have positive charge. This charged particle is called
ion ,positive ions are cations
Positive ions are formed when an atom loses electrons
When an atom has more electrons,it will have negative charge. Ions with negative charge is called anion
Elements of group 1 will have 1 electron in the outer most shell and all of the elements in group 1 lose 1
electron and they will have a charge of +1
Elements of group 2 will have 2 electron in the outer most shell and all of the elements in group 2 lose 2
electron and they will have a charge of +2
Elements of group 3 will have 3 electron in the outer most shell and all of the elements in group 3 lose 3
electron and they will have a charge of +3
Elements of group 4 will have 4 electrons in the outer shell, they share 4 electrons to have inert gas
configuration
Elements of group 5 will have 5 electrons in the outermost shell and they gain 3 electrons,they form
negative ions of charge -3
Elements of group 6 will have 6 electrons and they gain 2 electrons ,they form negative ions with -2 charge
Group 7 elements gain 1 electron and form negative ions with -1 charge
Formula of ionic compounds
Eg.
Ammonium carbonate-(NH4)2CO3
Sodium phosphate-Na3PO4