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General Chemistry

4.81 Which of these aqueous solutions would you expect to be the best conductor of electricity at 25° C? Explain your answer? (a) 0.20M NaCl (b) 0.60M CH3COOH (c) 0.25M HCl (d) 0.20M Mg (NO3)2

Multiple Choice Questions

6 ) Iron has a density of 7.86 g/cm3. The volume occupied by 55.85 g of iron is: 7 ) Which pair of elements would be most likely to form an ionic compound? P and Br Cu and K C and O O and Zn Al and Rb 8 ) Which is the formula for the binary compound of potassium and nitrogen? KN K2N NK2

Energy Released by a Reaction

I have been given the attached as a balanced chemical equation for the complete oxidation of one mole of oleic acid. 2CH3(CH2)7CH = CH(CH2)7COOH + 51)2 = 36CO2 = 36CO2 + 34H20 Using the following table how do I work out the energy released by the reaction? TYPE OF BOND AVERAGE ENERGY CONTENT/kJ mol-1 Single ca

Epitaxy, Berry's Rotation, Polarization, IR spectroscopy, Rochow

This is a past exam for practice. Please complete question 5 only. 20 5. Write brief notes on any four of the following: a. Metal-organic vapor phase epitaxy b. Berry's rotation. c. Effect of polarization on melting points d. IR spectroscopy as a tool for structure determination of inorganic compounds e. Rochow pr

Multiple choice

Out of 250 questions, I am unsure of the following: 1.For a given substance that exhibits liquid-crystalline properties, the transition from solid to liquid-crystal state occurs: a.over a range of temperatures that includes the melting point of the soild. b. at a well defined temperture above the melting point of the solid.

Bond Energies and DH

Using the table of bond energies to determine the DH for the reaction: 2H--F(g) H--H(g)+ F--F(g).

Bonding in coordination chemistry

Why do square planar geometries occur in d7, d8, and d9 ions with strong field- pi acceptor ligands, except in cases in which ligand geometry requires it?

Bonding in Co-Ordination chemistry

How is it possible that [Co(h20)6]3+ will oxidize water but [Co(Nh36]3+ is stable in aqueous solution? Both are mondentate ligands. I thought the proximity of the nitrogens after one has bonded to the cobalt would make it more likely to react, because the entropy would be lowered. They are also both low spin complexes.

Structures of Solids

My professor gave us this and told us that some of these problems will be on our test. I just want to make sure I know how to do all of them correctly. Thanks! 1. When describing structures of solids, especially ionic solids, structure types are typically associated with the structures of well-known species. If a system we

Solubility of Crystals - Inorganic Thermodynamics

The alkali metal hexachloroplatinates: Na2[PtCl6], K2[PtCl6], Rb2[PtCl6], Cs2[PtCl6] have the same type of lattice structure. How would you expect the solubility of these salts to vary (increase or decrease) from the sodium salt to the cesium salt? Explain your answer.

Predict the signs of q and w for the reaction

Please give complete answers and details on how to think about these problems. Also, explain reasoning on how you get your answer please! Predict the signs of q and w for the following: A. Condensing water in an exothermic process at P=1 atm and T=370K. H20(g) -> H20(l) B. Subliming CO2(dry ice) - an endothermic pro

Standard Heat of Formation, Kinetic Molecular Theory of Gases

7 general chemistry questions. Example: The reaction of silver metal and dilute nitric acid proceeds according to the equation above. If 0.10 mole of powdered silver is added to 10 milliliters of 6.0-molar nitric acid, the number of moles of NO gas that can be formed is: (a) 0.015 mole (b) 0.020 mole (c) 0.030 mole (d) 0

Boiling Point, Ideal Gas Equation, Critical Temperature

6 general chemistry questions - i.e. "Atoms of an element, X, have the electronic configuration shown above. The compound most likely to form with magnesium, Mg, is: (a) MgX (b) Mg2X (c) MgX2 (d) Mg2X3 (e) Mg3X2 " *(Please see attachment for complete equations and problems)

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