Category Archives: physics

Sun day in the Park with Gibbs; or, I have no life and it’s all CarnotCycle’s fault

There are many data tables out there, that are unfortunately not transcribed into usable form, but are stuck as images that cannot be searched. A thermodynamical blog, CarnotCycle, has provided some of these here.

Having no entertainments of any lasting value, I’ve decided to transcribe that one into a common format, Microsoft Excel (2007+ file format). They are here: CarnotCycle-Thermodata.

Although he claims they are in SI, they aren’t. SI does not use the calorie as a unit of energy, instead using the joule. Similarly with degree centigrade and kelvin. I have added a tab to convert the semi-SI to full SI. Digit significance has been maintained while doing this.

I do not know what book he got them out of, so I have to request you cite them as coming from his blog, for now. If you want to credit me with the transcription, that is fine. Use your preferred/recommended/required citation style to do this.

Some notes:

  • Some values were given in parenthesis. In Excel, parentheses are used to indicate a negative number in accounting. I changed this format to gray background with center-aligned numbers.
  • One value was given with a question mark. This is marked with a red background.
  • One value is suspiciously positive, I have marked this with a yellow background.
  • Where needed, scientific notation is use to maintain the correct number of significant digits.
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Idea for chemistry laboratory commissioning

Everyone who has ever taken a high school or college course in chemistry, biology or kindred sciences unquestionably remembers the, sometimes lurid, always present  warnings against doing things, normally, well, normal, but dangerous in a laboratory.1

Wear your safety glasses/googles.

No horsing around.

Label your experiments.

Clean up after yourself.

No food or drink.

This last one gave me an idea:

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A beautiful island of Science

There is a term in physics and somewhat chemistry, the “island of stability”. Essentially as atoms get bigger, they tend to be less stable. That is, they are radioactive and tend to decay into smaller atoms.

Except there is a suspicion that when they are large enough, they might get to be stable again. Here’s a map of this island, with mistakes, from a Wikipedian user:

1000px-Island_of_Stability.svgWITH MISTAKES!

The mistakes in question are of the proton and neutron numbers, so don’t use this on an exam.

Having said that, it is a beautiful illustration of the concept and the naming conceit. Anyone can see why it is an “island” in speech. The current image is more scholarly, but less attractive.