Applied Science BTEC level 3 Unit 1 Chemistry with complete solution

Ionic bonding Strong electrostatic attraction between oppositely charged ions What effect does ionic radius have on the strength of ionic bonding? The smaller the radius, the stronger the strength of the ionic bond. What effect does ionic charge have on the strength of ionic bonding? The higher the charge (the number) of the ions involved, the strong the ionic bond. Covalent bonding The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms Dative covalent bond A shared pair of electrons which has been provided by one of the bonding atoms only Bond length the average distance between the nuclei of two bonded atoms Bond Length and Strength Relationship The longer the bond length the weaker the strength of the bond, the easier it is to break the bond (uses less energy to break, making it a more reactive molecule) Tetrahedral bond angle 109.5 degrees Polar describes a molecule in which the positive and negative charges are separated Polar covalent bond A covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom, making it slightly negative and the other atom slightly positive. Tetrahedral Bond Shape The bond angle of 109.5 degrees allows the bonding electron pairs to sit as far apart as possible in the 3D structure. This is because of electron-electron repulsion. Metallic bonding properties De-localised electrons, positive metal ions in a regular layer structure. van der Waals forces a slight attraction that develops between the oppositely charged regions of nearby molecules dipole-dipole forces weak attractions between oppositely charged regions of polar molecules H-bonding Strongest intermolecular force. The slight positive charge on the H of the O-H bond is attracted to the slight negative charge on the H of the O-H bond on another molecule.