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.
When three electrons pairs get as far apart from each other, a trigonal planar structure is formed, as shown below. The bond angle in this structure is 120o.. Four electron pairs form a tetrahedron when they are separated as far as possible from each other. The bond angle in a tetrahedron is 109.5o. Five electron pairs form a trigonal bipyramid when they are separated in space.