This type of clothing should not be worn for parties, weddings and other formal or ceremonial events. They should not also be worn for work. Various items of clothing such as tee-shirts, denims, khakis, jackets, hoodies, mini-skirts, summer dresses, loafers, sneakers, and sandals are casual wear.
The presence of a lone pair decreases the bond angle between the bonding pair of electrons, due to their high electric charge which causes great repulsion between the electrons. They are also used in the formation of a dative bond.
Tetrahedral Bond Angles. The structure of organic molecules can be explained on the basis of valence bond theory or VSEPR (Valence shell electron pair repulsion theory). The valence bond theory is based on the concept of hybridisation. Hybridisation involves the mixing of atomic orbitals to form same number of hybrid orbitals.