27Oct 2014 by Vincent Summers No Comments

Anhydrides – Inorganic and Organic

Chemistry
Anhydrides are compounds that are similar to other compounds from which one or more molecules of water has been eliminated. An anhydride must not be confused with an anhydrous compound. In an anhydrous compound, the water reactant from which it is formed includes water that is attached lightly by weak bonds. Water is not an inherent part of the molecule's structure. Consider cupric sulfate pentahydrate, CuSO₄•5H₂O. This is a blue, crystalline substance. It is a composite structure of one molecule of cupric sulfate and five weakly held molecules of water of crystallization. Those water molecules can be removed quite easily. Powdering the crystals and warming them in a drying oven produces CuSO₄. This anhydrous compound is nearly white. No, it is not an anhydride. Aluminum Oxide Aluminum oxide, Al₂O₃, is an…
Read More
11Nov 2013 by Vincent Summers No Comments

Acid Base Proton Transfer

Chemistry
[caption id="attachment_20220" align="alignright" width="440"] Acetic acid dissociation[/caption] The concepts contained in this article sound complex: acid base proton transfer. But they are a lot simpler than they sound. If a hydrogen atom Hº is ionized by stripping off its one electron, what remains is a proton. This small positive particle, symbol H⁺, is the heart of acid base proton transfer reactions. But That's Too Simple In water, the H⁺ ion does not exist as a naked proton. Rather, it is united with a molecule of water in the form of a stabilized hydronium ion (H₃O⁺). So in aqueous solutions, hydronium ions are the proton donors. Acid Base Proton Transfer Proton transfer acceptors, rather than being proton poor, are electron rich. Still, since acids are proton donors, it logically follows that…
Read More