enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Molecular_geometry

    Molecular geometries can be specified in terms of 'bond lengths', 'bond angles' and 'torsional angles'. The bond length is defined to be the average distance between the nuclei of two atoms bonded together in any given molecule. A bond angle is the angle formed between three atoms across at least two bonds.

  3. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  4. Bent molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Bent_molecular_geometry

    AX 2 E 1 molecules, such as SnCl 2, have only one lone pair and the central angle about 120° (the centre and two vertices of an equilateral triangle). They have three sp 2 orbitals. There exist also sd-hybridised AX 2 compounds of transition metals without lone pairs: they have the central angle about 90° and are also classified as bent.

  5. Crystal structure - Wikipedia

    en.wikipedia.org/wiki/Crystal_structure

    The lengths of principal axes/edges, of unit cell and angles between them are lattice constants, also called lattice parameters or cell parameters. The symmetry properties of crystal are described by the concept of space groups. [1] All possible symmetric arrangements of particles in three-dimensional space may be described by 230 space groups.

  6. VSEPR theory - Wikipedia

    en.wikipedia.org/wiki/VSEPR_theory

    Shows location of unpaired electrons, bonded atoms, and bond angles. The bond angle for water is 104.5°. Valence shell electron pair repulsion ( VSEPR ) theory ( / ˈ v ɛ s p ər , v ə ˈ s ɛ p ər / VESP -ər , [ 1 ] : 410 və- SEP -ər [ 2 ] ) is a model used in chemistry to predict the geometry of individual molecules from the number of ...

  7. Adjacent - Wikipedia

    en.wikipedia.org/wiki/Adjacent

    Adjacent angles, two angles that share a common ray; Adjacent channel in broadcasting, a channel that is next to another channel; Adjacency matrix, a matrix that represents a graph; Adjacency pairs in pragmatics, paired utterances such as a question and answer; Adjacent side (polygon), a side that shares an angle with another given side

  8. Inscribed angle - Wikipedia

    en.wikipedia.org/wiki/Inscribed_angle

    The measure of ∠AOB, where O is the center of the circle, is 2α. The inscribed angle theorem states that an angle θ inscribed in a circle is half of the central angle 2θ that subtends the same arc on the circle. Therefore, the angle does not change as its vertex is moved to different positions on the circle.

  9. Circle - Wikipedia

    en.wikipedia.org/wiki/Circle

    The angle between a chord and the tangent at one of its endpoints is equal to one half the angle subtended at the centre of the circle, on the opposite side of the chord (tangent chord angle). If the angle subtended by the chord at the centre is 90°, then ℓ = r √2, where ℓ is the length of the chord, and r is the radius of the circle.