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Expressing resonance when drawing Lewis structures may be done either by drawing each of the possible resonance forms and placing double-headed arrows between them or by using dashed lines to represent the partial bonds (although the latter is a good representation of the resonance hybrid which is not, formally speaking, a Lewis structure).
Lewis structures (or "Lewis dot structures") are flat graphical formulas that show atom connectivity and lone pair or unpaired electrons, but not three-dimensional structure. This notation is mostly used for small molecules. Each line represents the two electrons of a single bond. Two or three parallel lines between pairs of atoms represent ...
The Simplified Molecular Input Line Entry System (SMILES) is a specification in the form of a line notation for describing the structure of chemical species using short ASCII strings. SMILES strings can be imported by most molecule editors for conversion back into two-dimensional drawings or three-dimensional models of the molecules.
The usual rules for constructing Lewis structures must be modified to accommodate molecules like triplet dioxygen or nitric oxide that contain 2c-3e bonds. There is no consensus in this regard; Pauling has suggested the use of three closely spaced collinear dots to represent the three-electron bond (see illustration). [8]
While these rules only apply to oxide glasses, they were the first rules to establish the idea of a continuous random network for glass structure. He was also the first to classify structural roles for various oxides, some being main glass formers (SiO 2 , GeO 2 , P 2 O 5 ), and some being glass modifiers (Na 2 O, CaO).
A valence bond structure resembles a Lewis structure, but when a molecule cannot be fully represented by a single Lewis structure, multiple valence bond structures are used. Each of these VB structures represents a specific Lewis structure. This combination of valence bond structures is the main point of resonance theory.
Lone pairs (shown as pairs of dots) in the Lewis structure of hydroxide. In chemistry, a lone pair refers to a pair of valence electrons that are not shared with another atom in a covalent bond [1] and is sometimes called an unshared pair or non-bonding pair. Lone pairs are found in the outermost electron shell of atoms.
Lewis Structure of H 2 O indicating bond angle and bond length. Water (H 2 O) is a simple triatomic bent molecule with C 2v molecular symmetry and bond angle of 104.5° between the central oxygen atom and the hydrogen atoms.