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Classification of Chemical Bond Types

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1.4 Classification of Chemical Bond Types

Types of Chemical Bonds

A group of atoms bonded to one another form a molecule.

If the molecule has more than one type of element present it is a compound.

Different types of bonds hold molecules and compounds together.
These 2 types of bonds are 1. ionic and 2. covalent.

Atoms start off with the same number of positive protons and negative electrons. This way the opposite charges cancel each other out.

Charged atoms, or ions, can form when atoms lose or gain electrons- remember that atoms will gain or lose electrons in order to have a full outer shell.
If an atom starts off with 9 protons and 9 electrons, the positive and negative charges are balanced out. However, this atom only has 7 electrons in its outer shell, so it wants 1 more electron to have 8 and be happy. But when the atom gains an extra negative electron, it now has 10 negative electrons and 9 positive protons. Therefore its overall charge is -1. If an atom has one electron in its outer shell, it will usually give that electron away and use the next lower shell as a "full" outer shell. When it gives a negative electron away, it becomes a positively charged ion.
Positive and negative ions are attracted to one another and bond together in ionic bonds.

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A salt is a dry solid composed of atoms connected by ionic bonds Ex- table

salt.

A covalent bond results when two atoms share electrons, thereby completing their valence shells

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