âSorry for the paucity of posts over the past few days but I'm in a state of upheaval known as âjob changeâ.â âThere is no scheme in all these projects to solve the paucity of clean, safe drinking water.â âThe paucity of these qualities in the present Republic would stagger them.â
Benzene is the archetypical aromatic compound. It is planar, bond angles=120Âº, all carbon atoms in the ring are sp2 hybridized, and the pi-orbitals are occupied by 6 electrons. The aromatic heterocycle pyridine is similar to benzene, and is often used as a weak base for scavenging protons.
1 As a result, they all have a tetrahedral arrangment of electron pairs around the central atom. 2  The bond angle in methane, CH 4, is the tetrahedral angle, i.e. 109.5 (109 28'). 3  Ammonia, NH 3, contains a lone pair of electrons, which repels the bonding electrons to give a bond angle of 107. The bond angle in methane, CH 4, is the tetrahedral angle, i.e. 109.5 (109 28'). 2  Ammonia, NH 3, contains a lone pair of electrons, which repels the bonding electrons to give a bond angle of 107. 3  The atoms have a trigonal pyramidal arrangement.