• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Document
Document

... The Modern Reassessment of the Atomic Theory 1. All matter is composed of atoms. The atom is the smallest body that retains the unique identity of the element. 2. Atoms of one element cannot be converted into atoms of another element in a chemical reaction. Elements can only be converted into other ...
Unit 1
Unit 1

... 7. To know that ionic compounds can be formed from their elements, but most often result from combination of ions that already exist in the ionic state. 8. To know that ionic bonds result from charge attractions between individual ions throughout a crystalline lattice, without significant sharing of ...
Chemistry Review Module Chapter 1
Chemistry Review Module Chapter 1

... Why? Because the least precise measurement had 3 significant digits, so our answer should not have more than 3 significant digits! The technique for addition and subtraction is slightly different (see p.396 ) but the concept is the same. You cannot make your result better than your measurements! ...
File
File

DFT Studies of the Zinc Complexes of DNA Bases
DFT Studies of the Zinc Complexes of DNA Bases

... DNA bases. This tendency is similar to that obtained for the alkali metal ion complexes, and it is shown that the ...
ORGANIC CHEMISTRY: The chemistry of carbon compounds
ORGANIC CHEMISTRY: The chemistry of carbon compounds

... 13 This compound is produced from benzene and is used in making a type of nylon: ____________________ 14. The radical formed from a benzene ring is the__________________ radical. 15. When alcohol is attached to a benzene ring, you have a sore throat spray called: ____________________________________ ...
Amines and Amides
Amines and Amides

... Primary and secondary amines have H atom attached to the N, therefore they are capable of intermolecular H-bonding. These forces are not as strong as those between alcohol molecules which have H bonded to O, a more electronegative element than N. This means that amines boils at lower temperature t ...
Document
Document

... (b) The anion sulfite is SO32-; therefore you need 2 Na+ for each sulfite. The formula is Na2SO3. (c) The ionic compound is barium hydroxide. When water is included in the formula, we use the term “hydrate” and a prefix that indicates the number of molecules of H2O. This compound is barium hydroxide ...
Epoxyalkyl peptide derivatives as active-site
Epoxyalkyl peptide derivatives as active-site

... inhibitors for this class of enzymes. Both compounds are derived from the basic sequence Arg-Asn-Gly-Yaa-Ala-Val-OMe, where Yaa represents epoxyethylglycine (I) and 2,3-epoxypropylglycine (11). Hence, these derivatives represent substrate analogues that are carrying a chemically reactive group at a ...
Document
Document

... (b) The anion sulfite is SO32-; therefore you need 2 Na+ for each sulfite. The formula is Na2SO3. (c) The ionic compound is barium hydroxide. When water is included in the formula, we use the term “hydrate” and a prefix that indicates the number of molecules of H2O. This compound is barium hydroxide ...
What`s in a Name? - Department of Chemistry | Washington
What`s in a Name? - Department of Chemistry | Washington

... naming acids. An acid is a proton donor. Therefore, for the purpose of nomenclature, an acid can be viewed as a molecule with one or more protons (H+) bonded to an anion. Note that the molecule must not carry a charge. For example, HSO3− is not an acid molecule; it is an anion because it carries a − ...
Carbon: The Backbone of Life
Carbon: The Backbone of Life

... Hydrocarbons  Hydrocarbons are organic molecules consisting of only carbon and hydrogen  Many organic molecules, such as fats, have hydrocarbon components  Hydrocarbons can undergo reactions that release a large amount of energy ...
Organic Chemistry : Ch. 19
Organic Chemistry : Ch. 19

... * Diagram a tertiary alcohol below: 2-methyl-2-propanol ...
Naming Hydrocarbons
Naming Hydrocarbons

... Hydrocarbons are named based on the family they are in (alkane, alkene, or alkyne), the length of the longest or main chain, the length of any shorter or side chains, and the location and number of any side chains or points of unsaturation. The family is shown by the suffixes ane, ene, and yne. As s ...
Chapter 17_CHEM 131
Chapter 17_CHEM 131

... • All monosaccharides with at least five carbon atoms exist predominantly as cyclic hemiacetals and hemiketals. • A Haworth structure can be used to depict the threedimensional cyclic carbohydrate structures. ...
Organic and Biochemistry
Organic and Biochemistry

... The acid involved in the peptide bond is named first. • Example: If a dipeptide is formed from alanine and glycine so that the –COOH group of glycine reacts with the –NH2 group of alanine, then the dipeptide is called glycylalanine. • Glycylalanine is abbreviated using a standard three-letter abbrev ...
Chapter 7 Ionic and Metallic Bonding
Chapter 7 Ionic and Metallic Bonding

... have to (Hund’s rule) ...
CrO3/Al2O3: Rapid oxidation of alcohols to carbonyl compounds in
CrO3/Al2O3: Rapid oxidation of alcohols to carbonyl compounds in

... and efficient method the alcohols were oxidized to the corresponding carbonyl compounds when the former was ground in a mortar with a pestle in the presence of supported CrO3 on Al2O3 and a few drops of tBuOH (Scheme I). The feasibility of the oxidation was first examined using benzyl alcohol as a m ...
Microsoft Word - Final Exam Study Guide
Microsoft Word - Final Exam Study Guide

Functional Groups and nomenclature Major concepts Stable
Functional Groups and nomenclature Major concepts Stable

... 9. Application to Medicine: Antihistamines are drugs commonly used to treat allergy symptoms. Newer antihistamines are blockbuster drugs because they do not cause drowsiness (due to the fact that they don’t cross the blood-brain barrier.) The structure of fexofenadine (Allegra) is shown below. How m ...
AP Biology
AP Biology

... ___ 44. Which of the following is a correct definition of a kilocalorie? a. The amount of heat required to raise 1 gram of water by one degree Fahrenheit. b. The amount of heat energy required to raise 1 gram of water by ten degrees Celsius. c. The amount of heat energy required to raise 1 kilogram ...
uplift luna ap chemistry
uplift luna ap chemistry

... is similar, except that anions are always made to end in -ate. Coordination compounds, like other ionic compounds, are named with the cation preceding the anion regardless of which (if either) one of them is a complex ion. The rules for naming complex ions or compounds are as follows:  As with any ...
File
File

... The dz2 and dx2y2 orbitals lie on the same axes as negative charges. Therefore, there is a large, unfavorable interaction between ligand (-) orbitals. These orbitals form the degenerate high energy pair of energy levels. The dxy , dyx and dxz orbitals bisect the negative charges. Therefore, there is ...
File
File

... carbon atoms) is combined with the ending "ene" to denote an alkene. Ethene, for example is the twocarbon molecule that contains one double bond. The chemical formula for the simple alkenes follows the expression CnH2n. Because one of the carbon pairs is double bonded, simple alkenes have two fewer ...
Picosecond  Flash  Photolysis  of Carbonyl  Complexes ... Ruthenium(II}  Porphyrin Cation  Radicals
Picosecond Flash Photolysis of Carbonyl Complexes ... Ruthenium(II} Porphyrin Cation Radicals

... This hypothesis has no validity, of course. if 2 and 3 are simply resonance structures of the same ground state. However. the differences in ionic radius and axial ligation expected between a ferric and ferrous complex could allow for an energy barrier between 2 and 3 so that 2 could be a discrete i ...
< 1 ... 71 72 73 74 75 76 77 78 79 ... 171 >

Homoaromaticity



Homoaromaticity in organic chemistry refers to a special case of aromaticity in which conjugation is interrupted by a single sp3 hybridized carbon atom. Although this sp3 center disrupts the continuous overlap of p-orbitals, traditionally thought to be a requirement for aromaticity, considerable thermodynamic stability and many of the spectroscopic, magnetic, and chemical properties associated with aromatic compounds are still observed for such compounds. This formal discontinuity is apparently bridged by p-orbital overlap, maintaining a contiguous cycle of π electrons that is responsible for this preserved chemical stability.The concept of homoaromaticity was pioneered by Saul Winstein in 1959, prompted by his studies of the “tris-homocyclopropenyl” cation. Since the publication of Winstein's paper, much research has been devoted to understanding and classifying these molecules, which represent an additional “class” of aromatic molecules included under the continuously broadening definition of aromaticity. To date, homoaromatic compounds are known to exist as cationic and anionic species, and some studies support the existence of neutral homoaromatic molecules, though these are less common. The 'homotropylium' cation (C8H9+) is perhaps the best studied example of a homoaromatic compound.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report