topic 2 bonding and structure

2 sperate atom displays with a dot or cross shown in the other atom square brackets and charges round atoms

shorter bonds are stronger as atoms are held closer so froce of attraction is stronger double and triplw bonds are shorter

a bond formed when the electron sin the shared pair are supplied from a single atom

strong electrostatic attraction between 2 + nuclei and the shared pair of electrons between them

electron pairs naturally repel eeavhother so that the largest bon dangle possible exists

each lone pair present adds additional repulsive forces and reduces bond angle betwen covalent bonds by 2.5 degrees

number of elecreon pairs how many are lone pairs and how many are bonding bonding = basic shape lone = additional repulsion

2 bond pairs 180

2 bond pair and 2 lone pairs 104.5

3 bond pairs 120

3 bond pairs 1 lone pair 107

4 bond pairs 109.5

5 bond pairs 90 and 120

6 bond pairs 90

the power of an atom to attract the electroj pair in a covalent bond towards itself

increases along a period as atomic radius decreases decreases down a group as shielding increases

difference in electronegativty between 0.4-1.7 it is a polar covalent

weakest instantaneous dipole induced froces greater the nm electrons the stronger teh froce straigth chains can pack closer so have stronger forces

polar bonds create permanant dipoles leading to the attraction of neighbouring molecules causing a lattice like structure

hydrogen and nitrogen, oxygen or fluorine lone pair on these atoms form a bond with a delta + hydrogen on another molecule

hudrogen bonds allow it to disolve ionic compounds by solvating ions can dissolve some alcohols by formin ghydroge bonds with hydroxyl group

water and alcohol cant dissolve some polar molecules that cant form hydrogen bonds non aqueous solvents are used fro compiounds which have the same type of intermolecular force

hydrogen fluroirde super high cause of hydrogen bonds then shoots down but slowly goes up as atomic number increases

greater cahrge is stronger larger sized atoms is weaker