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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

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

Structure of ice

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.

Ice substance

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)


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


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


Pls see attached

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

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


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?

Iconic Compounds

I am attaching a file. Please explain in detail how the solution is solved so I may compare. Thank You.

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


1.) How many bonds are present in propene, C3H6? 2.) How many bonds are present in acetylene, C2H2?

Behaviour of phosphorus pentachloride (PCl5)

PCl5 is a white solid, which volatilises at 160oC and melts at 148oC under pressure. Molten PCl5 conducts an electric current readily. At 180oC PCl5 vapour has a density of 9.3 g/L corrected to the standard conditions. At 250oC a sample of PCl5 exerts a pressure, which is twice the expected value. Discuss these observations and

Peptide Bonds

Draw the peptide Asn-Val-Ile-Cys and list the number of peptide bonds and what type of peptide is it (dipeptide, tripeptide etc...)?