Explore BrainMass
Share

Explore BrainMass

    Bonding

    Lewis formulas, valance electron drawings

    One of the steps in writing the Lewis formulas of covalently bonded molecules is to add up the total number of valance electrons from the atoms involved. What are the total number of of such electrons for the following? A)CH4 B) SO3 C)H2S D) NH3 E N2

    The Theoretical Radius Ratio vs. Real Parameters

    The alkaline earth oxides MgO and BaO adopt the rock salt (NaCl) structure with cell parameters a of 4.213 à... and 5.139 à.... Using 1.40 à... as the radius for the oxide ion: a) Calculate the radius ratios r(M2+) / r(O2-) for these compounds b) Using the radius ratio rule, indicate whether or not the value found are i

    Ionic Bonding Length Calculated

    A certain form of AgI adopts the zinc blend (ZnS & FCC) structure. The density of the salt is 5.69 g/cm3. a) Calculate the length of a side of the unit cell b) Calculate the distance between the Ag+ and the I- ions in the structure.

    Determining hybridization and molecular shape

    1.)For each of the following covalent compounds deduce their molecular shape and the possible hybridization of the central atom: a.) indium(I)iodide b.)tin(II)bromide c.)antimony tribromide d.)tellurium tetrachloride e.)iodine pentafluoride 2.) Determine the electron pair arrangement and the molecular shape according to

    Bond Order, Bond Angles and Electron-Dot Diagrams

    1) Assuming that it has similar molecular orbital energies to those of carbon monoxide, deduce the bond order of the NO+ ion. 2) construct electron-dot diagrams for a) oxygen difluoride b) phosphorus trichloride c) xenon difluoride d) tetrachloroiodate ion, ICl4^- 3) Construct an electron-dot diagram for th

    Molecule Shapes Expected

    What shape do you expect for each of the following molecules? See attached for multiple choice answers.

    Molecule Shapes

    What shape do you expect for molecules that meet the following descriptions? a) A central atom with two lone pairs and three bonds to other atoms. b) A central atom with two lone pairs and two bonds to other atoms. c) A central atom with two lone pairs and four bonds to other atoms.

    Octet Rule for Substances

    Which of the following substances contains an atom that does not follow the octet rule? See attached for multiple choice answers.

    Lattice Energy for CaH2

    Calculate the lattice energy for CaH2 (in kilojoules per mole) using the following information: Eea for H = -72.8 kj / mol Ei1 for Ca = +589.8 kj / mol Ei2 for Ca = +1145 kj / mol Heat of sublimation for Ca = +178.2 kj / mol Bond dissociation energy for H2 = +435.9 kj / mol Net energy change for the formation of CaH2 from

    Structure of Ice Diamond Compared

    Compare the structure of ice with the structure of diamond. If you rotate the structures just right, you will see distinct similarities, namely sp3 hybridization (of owygen and carbon, respectively) and the hexagonal arrangement of atoms. Given this similarity, explain why ice can be melted by applying pressure whereas diamond

    Ethanol/acetic acid

    Ethanol and acetic acid have very similiar molor masses and hoth exhibit hydrogen bonding. In which of these two compounds is hydrogen bonding a more significant component of the overall intermolecular forces? Support your answer using date from the Equilibrium Vapor Pressure.

    Convert Ice to Liquid Water by Applying Pressure

    Water is a substance with some very unusual properties. Based on a comparison of the water molecule and the structure of ice explain (a) why ice is less dense than water, and (b) why increasing pressure, within a certain temperature range, causes ice to melt. (c) why is it not possible to convert ice to liquid water by applyi

    Lidocaine Problem

    Lidocaine is thought to bind to receptors in its methylated form above. Identify in writing the atoms or groups in the above compound that could be involved in its binding to a receptor via... (See attachment for full question).

    Electronegatives

    State the type of bonding that is present in barium chloride,BaCl2(2 should be subscript- low down , can't do it in this program), giving your reasons in two or three senttences, using arguments based on electronegatives. Also, give an explanation using electron stuctures, of the way in which the type of bonding explains the

    mechanism for the reaction

    Give a detailed mechanism for the reaction of o-fluorobenzophenone (Ar-C-(=O)-Ar-F)....Ar=benzene ring with amide ion (NH2/NH3) to yield H2N-C(=O)-Ar + Ar-F

    Bond Aluminum Foil Dissolved

    1. A. It takes 3.98x10-19 Joules to break the bond in a single Cl-Cl molecule. Will a photon of electromagnetic radiation with a wavelength of 400 nanometers provide sufficient energy to break such a bond? B. Will a piece of aluminum foil dissolve in a water solution containing silver ions? Give a reason for your ans

    Four compounds have the formula C4H8O, identify possible compounds.

    Four compounds have the formula C4H8O. Identify possible compounds (by name or structure). Compounds A and C have similar boiling points; Compounds B and D have significantly lower boiling points than A and C. A Reacts with oxidizing agents; reacts immediately with bromine; negative Iodoform Test; negative Lucas Test. B

    Reaction Enthalpy and Bond Energy

    Using H-H 432.0, Cl-Cl = 239.7, H-Cl = 428.0, determine the rH for the reaction: H?H (g) + Cl?Cl(g) 2H?Cl (g) 2. If the rH of combustion of CH4 is -802kJ/mol. How many grams of water, which has a specific heat of 4.184 J/g-oC, can be heated from 20oC to 90oC by combustion of 2.00 mol o

    Pi bonding, temperature volume

    1) Two flexible containers for gasses are the same temperature and pressure. One holds .50 grams hydrgen and the other 8.0 grams of oxygen. Which of the following statements regarding these gas samples is false? a) the volume of the hydrogen container is the same as the volume of the oxygen container b) the number of mol

    Bond length, moles and cathodes

    1) Which of the following molecules has the shortest bond length a) N sub 2 b) O sub 2 c) Cl sub 2 d) Br sub 2 e) I sub 2 2) What number of moles of Osub2 his needed to produce 14.2 Grams 0f Psub4Osub10 (molecular mass =284g)from P? 3) If 0.060 faraday is passed through an electrolytic cell containing a solution of

    Elements Covalent Bonding Networks

    Questions 7 - 8: a) a network solid with covalent bonding b) a molecular solid with London dispersion forces only c) a molecular solid with hydrogen bonding d) an ionic solid e) a metallic solid 7) solid ethyl alcohol, Csub2Hsub5OH. Ans A, B, C, D or E? 8) silicon dioxide, SiOsub2. Ans A, B, C, D or E?

    Chemical Bonding

    I have been having trouble figuring out how to do problems 8-10 in the attachment below. I completed the problems, but I would like to make sure that I have the correct answers and that I understand the solutions to the problems.

    Band Structure Diagrams

    See attached problem. I am having trouble on all parts of the problem. Any assistance would be appreciated.

    Chemistry Problem Set: Half-Reactions

    Please see the attached file for full problem description. 2. Which half-reactions represent oxidation and which reduction? Explain your reasoning. 2+ - a. Fe --> Fe + 2 e 4+ _ 2+ b. Ni + 2 e --> Ni - - c

    Compounds & Structural Formulas, etc.

    Please see the attached file for full problem description. A popular brand of low-fat shredded cheddar cheese advertises that it provides 1.5 g of fat with 15 Calories from total fat per serving. There are 50 Calories per serving and of the total fat, 1.0 g is saturated fat. A serving is defined as ¼ cup or 28 g. Is this "lo

    Density, Conductivity, Coal-Combustion Calculations

    Question 15: The density of liquid water at 0 degrees C is 0.9987 g/cm cubed; the density of ice at this same temperature is 0.917 g/cm cubed. a. Calculate the volume occupied at 0 degrees C by 100. g of liquid water and by 100. g of ice. b. Calculate the percentage increase in volume when 100. g of water freezes at 0 degree

    Elements in atmosphere in pure form

    Which group of elements is normally obtained from the atmosphere in pure form? a) sulfur, phosphorus, oxygen, nitrogen b) magnesium, sodium, calcium, strontium c) flourine, chlorine, neon, argon d) flourine, chlorine, oxygen, nitrogen e) oxygen, nitrogen, neon, argon