bonding
...um (Al) 2,8,3 Silicon (Si) 2,8,4 Phosphorus (P) 2,8,5 Sulphur (S) 2,8,6 Chlorine (Cl) 2,8,7 Argon (Ar) 2,8,8 Potassium (K) 2,8,8,1 Calcium (Ca) 2,8,8,2 Ionic Bonding: Ionic bonding is the bonding of metals and non-metals. I.e. a transfer of electrons from a metal to a non-metal occurs. An Ionic bond is the electrostatic attraction between the ions of opposite charge and the structure formed is called a Lattice or Giant Ionic. During this transfer process atoms become charged. The positive ion is known as the cation and the negative anion. Metals (Group 1, 2, and 3 elements) lose electrons to get full outer shells and become positive ions. Example: Magnesium Fluoride 1e- Mg 2,8,2 = 12 F 2,7 =9 1e- F 2,7 =9 Mg becomes Mg 2+ as it has lost 2e- = Mg2+ [2,8] 2+ F becomes 2F- as it has gained 2e- = 2F- [2,8] – Therefore the formula becomes MgF2 2+ 2 Covalent Bonding: Covalent bonds form between atoms of non-metals. A covalent bond is a shared pair of electrons between two atoms. Each atom contributes one electron. Once bonded together the two atoms form a diatomic molecule. Definition: A diatomic molecule refers to a small particle containing two atoms covalently bonded together. Example: Hydrogen Chloride: H 1 Cl 2,8,7 Forms HCL 2,8,8 A single covalent bond is when two electrons are shared. Oxygen: O 2,6 O 2,6 Forms O2 A double covalent bond is when four electrons are shared. Hydrogen Bonding: Hydrogen bonding is another important type of noncovlaent bonding. Also referred to as dipole-dipole interaction. When electrons are shared between atoms in a chemical bond, they don’t have to be shared equally. Those with unequal sharing of atoms are referred to as polar. The action of an atom attracting electrons to itself in a chemical bond is known as Electronegativity. Oxygen is highly electronegative and the difference between oxygen and hydrogen in the O-H bond in water is such that oxygen, the larger of the two elements, has the larger share of the electrons. The difference in electronegativity between O and H gives a partial positive and negative charges (Known as S+ and S-) Therefore the O-H bond is polar. When hydrogen is covalently bonded to an electronegative atom such as oxygen, it has a partial positive charge due to the polar bond. This partial positive charge can interact with an unshared, non-bonding, pair of electrons (negative) on another electronegative element. All three atoms lie in a straight line forming a hydrogen bond. There are two types: Linear and non-linear. Hydrogen bonds are much weaker than normal covalent bonds. The Periodic Table From The Periodic Table it can be seen that the Period number gives the number of shells of electrons, which atoms have in that Period. For example Oxygen as it is Period two, so therefore has two shells of electrons. With six electrons in the second shell giving its electron structure 2,6. The number of electrons in the outer shell of an element is always the same as the group number. For example Sodium has one electro...