CHEMICAL BONDS AND REACTIONS
1) Chemical Bonds
A bond is the electrical attraction that holds two atoms together, just like the bond between two oppositely charged magnets. The attraction is created by the number of electrons in the outer shell of an atom to the protons in the nucleus of the other atom. Valence shell : the outer most electron shell of an atom. The 1 st shell always only contains 2e- but the 2 nd + shells will contain up to 8e-. Octet Rule : Chemical stability occurs when an atom has 2/8e- in its valence shell – always want to fill the valence shell.
Example:
Types of Bonds
a) Ionic Bond: a chemical bond between an anion and a cation.
Attraction that holds oppositely charged ions together. “Opposites attract – Dating”
Example:
b) Covalent Bond :
Attraction between atoms that share electrons.
Strongest Bond and much more common in the body.
Single Covalent bond: Share 1 pair
Double Covalent bond: Share 2 pairs
Triple Covalent bond: Share 3 pairs
Example:
Nonpolar Covalent Bond: equal sharing of e-
Example:
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