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  2. VSEPR theory - Wikipedia

    en.wikipedia.org/wiki/VSEPR_theory

    VSEPR theory is used to predict the arrangement of electron pairs around central atoms in molecules, especially simple and symmetric molecules. A central atom is defined in this theory as an atom which is bonded to two or more other atoms, while a terminal atom is bonded to only one other atom.

  3. Tetrahedral molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Tetrahedral_molecular_geometry

    In the gas phase, a single water molecule has an oxygen atom surrounded by two hydrogens and two lone pairs, and the H 2 O geometry is simply described as bent without considering the nonbonding lone pairs. [citation needed] However, in liquid water or in ice, the lone pairs form hydrogen bonds with neighboring water molecules. The most common ...

  4. Molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Molecular_geometry

    This shape is found when there are four bonds all on one central atom, with no extra unshared electron pairs. In accordance with the VSEPR (valence-shell electron pair repulsion theory), the bond angles between the electron bonds are arccos(− ⁠ 1 / 3 ⁠) = 109.47°. For example, methane (CH 4) is a tetrahedral molecule.

  5. Molecular model - Wikipedia

    en.wikipedia.org/wiki/Molecular_model

    A given atom would have solid and hollow valence spikes. The solid rods clicked into the tubes forming a bond, usually with free rotation. These were and are very widely used in organic chemistry departments and were made so accurately that interatomic measurements could be made by ruler.

  6. Trigonal pyramidal molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Trigonal_pyramidal...

    In chemistry, a trigonal pyramid is a molecular geometry with one atom at the apex and three atoms at the corners of a trigonal base, resembling a tetrahedron (not to be confused with the tetrahedral geometry). When all three atoms at the corners are identical, the molecule belongs to point group C 3v.

  7. Methyl formate - Wikipedia

    en.wikipedia.org/wiki/Methyl_formate

    In the laboratory, methyl formate can be produced by the condensation reaction of methanol and formic acid, as follows: . HCOOH + CH 3 OH → HCOOCH 3 + H 2 O. Industrial methyl formate, however, is usually produced by the combination of methanol and carbon monoxide (carbonylation) in the presence of a strong base, such as sodium methoxide: [4]

  8. List of gases - Wikipedia

    en.wikipedia.org/wiki/List_of_gases

    This list is sorted by boiling point of gases in ascending order, but can be sorted on different values. "sub" and "triple" refer to the sublimation point and the triple point, which are given in the case of a substance that sublimes at 1 atm; "dec" refers to decomposition. "~" means approximately.

  9. Square antiprismatic molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Square_antiprismatic...

    This shape has D 4d symmetry and is one of the three common shapes for octacoordinate transition metal complexes, along with the dodecahedron and the bicapped trigonal prism. [2] [3] Like with other high coordination numbers, eight-coordinate compounds are often distorted from idealized geometries, as illustrated by the structure of Na 3 TaF 8.