Explore BrainMass

Explore BrainMass


    Chemical Structure describes both the molecular geometry and the chemical bonds which link individual atoms together. The molecular geometry refers to the spatial arrangement of individual atoms within a three dimensional space. Such arrangements are usually determined by the chemical bond which is present, and the valency of the composing atoms.

    Chemical structures may vary depending on the type of atom, element, and chemical bond. For example, covalent bonds between atoms form molecular structures, while ionic bonds between ions form crystal lattices, where a specific pattern and symmetry is usually observed. In addition, most chemical structures can then interact with other chemical structures to form larger structures; thus, forming a hierarchy of structures.

    By using the Valence Shell Electron Pair Repulsion (VSEPR) theory, the geometry of a molecule can be determined through the degree of electrostatic repulsion between electron pairs within the molecule. For example, methane with a chemical formula CH4 does not have any nonbonding electron pairs, so equal repulsion takes place between each C-H bond, causing the molecule to take the natural form of a tetrahedral in a three dimensional space. On the other hand, ammonia, with a chemical formula NH3, has one nonbonding electron pair, and so it repulses the three N-H bonds more strongly than a typical N-H electron pair, causing the molecule to take the shape of a thin triangle-based pyramid.

    Molecular structures can be determined by a multitude of experimental methods, whether they are conducted independently or in conjunction. For example, X-ray crystallography can be used independently to determine the atomic and molecular structure of crystals, by recording the direction of diffracted X-ray beams. Thus, understanding chemical structures, whether they are molecular or crystalline is crucial for understanding different chemical phenomena.

    © BrainMass Inc. brainmass.com May 23, 2024, 1:45 am ad1c9bdddf

    BrainMass Solutions Available for Instant Download

    ChemBio3D: Building of 3D and 2D structural models of Prozac

    In the first part of this tutorial, we are building the Prozac molecule with and without H+ atoms. We show how to copy high quality images from CHEMBIO3 into a text editor as bitmaps. Then we will identify the stoichiometry of the molecule (the enantiomer we are working with). We will then obtain the 2D version of the Prozac mol

    Cations and anions lab

    This is a lab report that centers around the reaction between cations and anions. The resulting precipitate is indicative of the reaction that occurred. In our lab a lead nitrate solution, Pb(NO3)2 will be mixed with a solution of potassium chromate, K2CrO4, a yellow precipitate will forms. Though I have completed this lab,

    Electron configurations, Redox reactions, Lewis structures

    1. Write an electron configuration for N ,and draw the Lewis structure for N. 2. Add single electron dots and/or pairs of dots as appropriate to show the Lewis symbols of the following neutral atoms. As, Se, Br, K, Ca, and Ga 3. If the following elements were involved in redox (electron transfer) reactions, which noble-gas (He

    Chemistry: Molecular Structures

    1. [Co(en)2(C2O4)]+ What's the Coordination number: 2. Draw the two geometric isomers of [Co(NH3)3Cl3]2+ (Add wedges/ dashes, etc.) 3. Draw the structural Formula: a) 2, 5-dimethylnonane b) 3-ethyl-4, 4-dimethylheptane c) 1-ethyl-4-methylcyclohexane 4. (See attached picture, requires structural drawing)

    Solid State Chemistry: Lattice Energy

    1) Estimate the radius of the cesium ion, Cs+. The lattice energy of cesium chloride, CsCl, is 633kJ/mol. For CsCl, the Madelung constant M is 1.763, and the Born exponent n is 10.7. The radius of Cl - is known to be 1.81 A. Express your answer in Angstroms. 2) Chlorofluorocarbons (CFC's) are organic compounds that have been


    In the name "trichloromethane", why wouldn't one use numbers, naming it "1,1,1-trichloromethane"?

    Geometric isomer sketching

    [ Pd (H2O) (CO) (CN) I ] SO3 1. DRAW the isomers of this compound, and label them as geometric or optical (enatiomers): i.e. Use the [ ]SO3 *the drawing would be inside the brackets. sodium Diamminedioxalatochromate (III) 2. DRAW the isomers of this compound, and label them as geometric or optical (enatiomers):

    Nomenclature and Molecular Shapes

    Please see the attached file for the entire problems. 1. Naming Covalent Compounds Part A What is the name of the covalent compound CCl4 ? Part B What is the name of the covalent compound N2O5? 2. Octet Rule and Ions Part A Construct an orbital diagram to show the electron configuration for a neutral magnesium at

    Electronic Configuration for Silicon

    Write an electronic configuration for each of the following elements, using the form 1s^2s^2p^6, and so on. Indicate how many electrons are unpaired for Silicon and element 37.

    Polar and Non-Polar Solutes

    How do you tell if a substance, KCL, for example, is ionic? Explain in most simple terms exactly what makes an ionic compound dissolve in water, and how do you know if a substance to be dissoloved is polar, or non polar? I know that water is polar, but get lost after that. Thanks.

    Simple Solids - Structures

    1. Draw one layer of close-packed spheres. On this layer mark the positions of the centers of the B layer atoms using the symbol X and, with the symbol O mark the positions of the centers of the C layer atoms of an fcc lattice. 2. Consider the structure of rock salt. (a) What are the coordination numbers of the anion and cati

    Magnetic Structures in Relation to Properties

    I know that [Ni(CN)4]2- is diamagnetic and square planar in shape. [NiCl4]2- is paramagnetic and tetrahedral in shape. Since these are two completely different complexes (I am assuming), why or what about their magnetic structures/properties is worth highlighting to show the differences between the two?

    Tetrahedral Sites in Cubic Cell

    I am having trouble with the whole problem. Calculating the distance between tetrahedral sites and drawing the unit cell and whether the tetrahedra share vertices, edges or faces. The actual problem is attached.