The Fascinating Kitchen Physics of Boiling Water

Chemistry, Physics
[caption id="attachment_23534" align="alignright" width="480"] Image by Jeshoots[/caption] Cutting-edge science is fascinating. Yet the science of everyday life is anything but boring. Consider the simple act of boiling water on the kitchen stove. There are many factors that come into play leading to the production of steam. Let's take a close look at water as an individual molecule and as a cluster of interacting molecules. Water at the Molecular Level Water consists of one oxygen atom plus two hydrogen atoms. An atom of oxygen is much larger than one of hydrogen. Most hydrogen atoms consist of a lone electron in orbit about a single proton nucleus. Oxygen atoms have a much larger nucleus orbited by 8 electrons. Oxygen has a strong affinity for electrons. So it is an electronegative element. On…
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Transition from Ice to Water to Vapor

[caption id="attachment_5490" align="alignright" width="440"] Hydrogen Bonding - CCA SA 3.0 Unported by Magasjukur2[/caption] The transition from ice to water to steam. What happens? A block of ice has a temperature well below freezing and is warmed gradually. It reaches above the boiling point. What transitions occur along the way? What are the processes? Transition: Solid to Liquid At first, the heat supplied simply increases the temperature of the ice. The temperature of the surface is somewhat warmer than the ice inside. It takes time for heat to penetrate. Eventually, the outer layer of the ice reaches the melting point. The outside ice melts first—then the inner ice. [caption id="attachment_5491" align="alignleft" width="220"] Melting Ice[/caption] During melting, the heat energy is spent breaking the stiff hydrogen bonds. None of it is spent…
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On the Nature of Azeotropes

[caption id="attachment_4850" align="alignright" width="440"] Russian Vodka Still[/caption] Definition: azeotropes are a specific mixture of compounds that boil together as if they were a single substance, at constant temperature. Individual Boiling Points In most instances, liquids boil as pure substances at a specific temperature. It is this property that allows boiling (as a physical property) to be used as a means of separation. For instance, an ester may be produced by reacting an organic acid and an alcohol. The resultant ester may usually be separated by boiling from excess alcohol or excess acid. Yet, Occasionally In some instances, however, as for example in the case of ethyl alcohol and water, there may be a mixture that distills over, instead of a pure substance. Thus a “mixture” of approximately 95.6% alcohol and…
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