The wash bottle


Washbottles, old (left, photo: Hannes Grobe) and new (right).

Wash bottles, in one form or another, have been a long-term feature of the chemistry lab. Once they were made of glass, and were operated by blowing. In more recent times, plastic squeeze bottles have been used.

See here for more posts on scientific equipment.


Blue Jeans and Culture

An earlier post touched on the concept of “cultural appropriation.” This label is often applied inappropriately, because the world is more interconnected than most people realise. It has been that way for longer than most people realise (for example, some 4,000 years ago, tin from England was being traded across the Mediterranean sea for use in making bronze). And ideas go back further than most people realise.

As Michael Crichton says in his excellent novel Timeline, “Yet the truth was that the modern world was invented in the Middle Ages. Everything from the legal system, to nation-states, to reliance on technology, to the concept of romantic love had first been established in medieval times. These stockbrokers owed the very notion of the market economy to the Middle Ages. And if they didn’t know that, then they didn’t know the basic facts of who they were. Why they did what they did. Where they had come from.

Consider blue jeans, for example.

Blue jeans are dyed with indigotin, a chemical derived from the indigo plant, which has long been grown in India. But before someone says “cultural appropriation from India,” indigotin was traditionally derived in Europe from the woad plant (northern Britons painted their skins blue with woad). In China, a different plant was used. Essentially, the use of indigotin was a cultural universal. In Germany, where a culture of excellence in organic chemistry grew up during the 19th century, a practical method for making synthetic indigotin was developed at the BASF company in 1897, and the choice of plant became moot.


A cake of indigo dye (photo: David Stroe)

Blue jeans are made from denim, a fabric named after Nîmes in France. During the California gold rush, Levi Strauss, a Jewish-American businessman of German origin, teamed up with Jacob Davis, a Jewish-American tailor of Latvian origin, to make denim work clothing for miners. These blue jeans were strengthened by metal rivets – an idea due to Davis, patented in 1873.

So which culture produced blue jeans – Indian? French? German? Latvian? Jewish? American? One can only say that blue jeans were produced by human culture.


Illustration from the patent application


A sample of elements

  • Helium (He, element 2) – used in balloons, because it is lighter than air
  • Carbon (C, element 6) – one of the key elements in living things
  • Nitrogen (N, element 7) – makes up 78% of the atmosphere
  • Oxygen (O, element 8) – makes up 21% of the atmosphere
  • Aluminium (Al, element 13) – a light metal used to make saucepans and aeroplanes
  • Silicon (Si, element 14) – used to make electronics
  • Phosphorus (P, element 15) – used in elemental form on the side of matchboxes
  • Sulfur (S, element 16) – a widely used element which occurs naturally in elemental form
  • Titanium (Ti, element 22) – a light, strong metal
  • Iron (Fe, element 26) – the most widely used metal (mixed with other elements it becomes steel)
  • Copper (Cu, element 29) – a metal that has been used for about 10,000 years, named after the island of Cyprus
  • Zinc (Zn, element 30) – used in batteries and to prevent corrosion
  • Silver (Ag, element 47) – widely used in jewellery since ancient times (the symbol is from the Latin argentum)
  • Tin (Sn, element 50) – about 5,000 years ago, tin (Latin stannum) was mixed with copper to produce bronze
  • Iodine (I, element 53) – dissolved in alcohol, it is used as a disinfectant
  • Gold (Au, element 79) – widely used in jewellery since ancient times (the symbol is from the Latin aurum)

For more on the elements, see the fantastic book The Elements by Theodore Gray of periodictable.com, which I have previously reviewed.


Chemical Compounds: the board game!

I have previously mentioned my strong interest in science / technology / engineering / mathematics education and in networks and in board games. This has prompted me to start designing educational games, such as the World Solar Challenge game. Joining the collection is my new Chemical Compounds game, which looks like this:

The online game store (faciliated by the wonderful people at The Game Crafter) has a free download link for the rules, should anyone wish to take a look. I also have a few other educational games there.


New element names

The IUPAC has just announced names for elements 113, 115, 117, and 118, which were temporarily named Ununtrium, Ununpentium, Ununseptium, and Ununoctium. The new names are:

The names still need final confirmation, but here (ta da!) is the new periodic table:

(Periodic table produced using R. Click to zoom.)


The dose makes the poison (part 2)

This periodic table summarises daily upper intake limits for various elements (data taken from a variety of sources). Of the elements highlighted, Thallium is the most toxic. However, some of these elements, like copper, are essential minerals for which there is also a recommended daily intake. Remember, the dose makes the poison.

Periodic table produced using R. Click to zoom.

Important note: these limits are for the most common form of elemental intake, e.g. sodium salts, phosphates, chlorides. One would not want to ingest Na, P, or Cl in elemental form!


Four new elements

This is old news, but earlier this year we had official confirmation of four new elements (temporarily named ununtrium, ununpentium, ununseptium, and ununoctium), thus completing the seventh row of the periodic table. Dmitri would be proud!

(Periodic table produced using R. Click to zoom.)