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Completing Energy Calculations

Determine the total amount of energy lost when 35 g of water are cooled from 135 degrees C to 25 degrees C. Lable each of the six steps and show me the equations and calculations.

Oxidization number

How can you tell the oxidation number of various elements such as Mn in MnO4, and N in NO3- and how can you tell what signifies the oxidizing agent and what signifies the reducing agent?

What is the importance of chemistry when talking about Chlamydia

I am looking for information involving the chemicals involved in maintaining the cellular wall integrity pre-host cell replication. I already have some information about disulfide bonds and sugar gateways in the pre-host cell membrane. Other searches have directed my attention to anti-oxidants (ascorbic acid) and the effects

Intramolecular H bond

1,3 Propanediol, HOCH2CH2CH2OH can form intra H bonds and inter molecular H bonds. Draw the structure of 1,3 Prop. that shows an intramolecular H bond. What does the 1,3 mean?

Molecular Geometry and Bonding

The basis of the VSEPR model of molecular bonding is ____________. a. regions of electron density on an atom will organize themselves so as to maximize s-character b. atomic orbitals of the bonding atoms must overlap for a bond to form c. hybrid orbitals will form as necessary to,

Finding alcohol formulae

Both my mum and I have looked everywhere and cannot find what I need. I have to find the alcohol formulas for; Methanol, Ethanol, Propanol, Butanol, Pentanol, Hexanol, Heptanol and Octanol. We have found chemical tables and compounds but not specifically any containing alcohol. Please can you help or tell me where i could loo

Orbitals, subshell, pressure, and chemical formula

Please help with the following questions. Question 6 The formula CH3CH2CH2=CH2 represents an alkene an alkyne an alcohol benzene Question 7 The number of orbitals in a d subshell is: 1 2 3 5 7 Question 8 _____ is credited with the modern structure of the

Molecular Geometry

For each molecule, draw the Lewis structure first, then apply the VSEPR model according to the following rules: 1. Count the number of electron pairs around the central atom (both bonding pairs and unshared pairs). Treat double and triple bonds as if they were single bonds. 2. Refer to the table given below to predict the geom

Naming Binary Ionic and Molecular Compounds

I need to write an essay that explains how a given set of names for binary ionic and molecular compounds can be determined. For an example let's pick KF which is potassium flouride. How can that name be found? I also need to discuss the nomenclature and chemical formulas in this essay by distinguishing between them. Wh

A complete molecular diagram fo C2 2- and determine the bond order.

The problem to solve is to formulate in which way two carbon atoms are described by using atomic orbitals. First one has to find out the electronic structure of a carbon atom by locating this element in the periodic table. Second step is then to fill the orbitals with the given number of electrons using Hund's rule. The third

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

Practice exam

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 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

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.


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

Don't understand

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