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  2. Ball-and-stick model - Wikipedia

    en.wikipedia.org/wiki/Ball-and-stick_model

    Hofmann's 1865 ball-and-stick model of methane (CH 4). Later discoveries disproved this geometry. In 1865, German chemist August Wilhelm von Hofmann was the first to make ball-and-stick molecular models. He used such models in lecture at the Royal Institution of Great Britain. Specialist companies manufacture kits and models to order.

  3. Tetrahedral molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Tetrahedral_molecular_geometry

    In a tetrahedral molecular geometry, a central atom is located at the center with four substituents that are located at the corners of a tetrahedron.The bond angles are arccos(− ⁠ 1 / 3 ⁠) = 109.4712206...° ≈ 109.5° when all four substituents are the same, as in methane (CH 4) [1] [2] as well as its heavier analogues.

  4. Molecular model - Wikipedia

    en.wikipedia.org/wiki/Molecular_model

    Molecular models may be created for several reasons – as pedagogic tools for students or those unfamiliar with atomistic structures; as objects to generate or test theories (e.g., the structure of DNA); as analogue computers (e.g., for measuring distances and angles in flexible systems); or as aesthetically pleasing objects on the boundary of ...

  5. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    [1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [ 4 ] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.

  6. Skeletal formula - Wikipedia

    en.wikipedia.org/wiki/Skeletal_formula

    The skeletal formula of the antidepressant drug escitalopram, featuring skeletal representations of heteroatoms, a triple bond, phenyl groups and stereochemistry. The skeletal formula, line-angle formula, bond-line formula or shorthand formula of an organic compound is a type of molecular structural formula that serves as a shorthand representation of a molecule's bonding and some details of ...

  7. Molecular geometry - Wikipedia

    en.wikipedia.org/wiki/Molecular_geometry

    For example, methane (CH 4) is a tetrahedral molecule. Octahedral: Octa-signifies eight, and -hedral relates to a face of a solid, so "octahedral" means "having eight faces". The bond angle is 90 degrees. For example, sulfur hexafluoride (SF 6) is an octahedral molecule.

  8. VSEPR theory - Wikipedia

    en.wikipedia.org/wiki/VSEPR_theory

    The methane molecule (CH 4) is tetrahedral because there are four pairs of electrons. The four hydrogen atoms are positioned at the vertices of a tetrahedron, and the bond angle is cos −1 (− 1 ⁄ 3) ≈ 109° 28′. [16] [17] This is referred to as an AX 4 type of molecule. As mentioned above, A represents the central atom and X represents ...

  9. Methane clathrate - Wikipedia

    en.wikipedia.org/wiki/Methane_clathrate

    Methane clathrate (CH 4 ·5.75H 2 O) or (4CH 4 ·23H 2 O), also called methane hydrate, hydromethane, methane ice, fire ice, natural gas hydrate, or gas hydrate, is a solid clathrate compound (more specifically, a clathrate hydrate) in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice.