Which are Stronger? Covalent or Ionic Bonds?

Chemistry, Physics
Almost all the atoms found in nature, left alone to themselves, are stable structures. If they always remained such, there would be no need of chemists. Fortunately, when in close contact, atoms can react in a number of ways. Often they link to each other in various combinations through bonding, forming molecules called compounds. Such interaction requires explanation, and so provides employment to humans educated in this field: The field called chemistry. Chemical Bonds: Ionic and Covalent There are a variety of ways atoms bond to one another. Some bonds are weaker, and some are stronger. Two of the strongest forms of chemical bond are the ionic and the covalent bonds. Chemical bonds form between two atoms, each with its own electron environment. If each of the two atoms shares…
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The Aromatic Cyclopentadienyl Anion

Chemistry, Education
[caption id="attachment_16480" align="alignright" width="440"] Cyclopentadienyl Anion[/caption] Is it possible that for an ion to be aromatic? Yes. Consider the aromatic cyclopentadienyl anion. Hückel’s Rule dictates a flat ring with 4n + 2 π (pi) conjugated electrons. The smallest neutral ring with these qualifications has n = 1. It is benzene (C₆H₆). But Hückel’s law does not require an electronically neutral structure. The smallest aromatic ion is the cyclopropenyl cation¹ (C₃H₃⁺). Is there a negative ion that has 6 π electrons and is aromatic? The answer is yes. The aromatic cyclopentadienyl anion (C₅H₅⁻). Neutral Cyclopentadiene Neutral cyclopentadiene is flat. It is pentagon shaped. Three of the carbon-carbon bonds are single bonds. The other two are double bonds. At each of the four ends of the two double bonds there is one…
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