19 April 26

As chemists and physicists produced new elements from the 1940s through today, there have been frequent controversies over the official names for the additions to the periodic table. These were mostly tied to rival claims for discovery and identification. Element 106 was first created in 1974, and was initially known as "unnilhexium," a Latin-based string for the number 106. To honor the nuclear chemist Glenn Seaborg, who had been a pioneer for plutonium and several other elements, the American discoverers proposed the name seaborgium, but there was a standing rule against names for living scientists. Twenty years later that rule was relaxed, and the name seaborgium was officially recognized in 1997. My periodic table tie honors Glenn Seaborg's birthday on this date in 1912. He died in 1999.

22 October 24

Tomorrow (10-23) marks the annual Mole Day chemfest. I'm celebrating a day early because I am attending a special lunch for Berea Home Village and the organizer wondered what tie I would wear! Mole Day is special to chemists because its date (10-23) corresponds with the exponential part of Avogadro's Number (6.02 x 10**23), which is how many things (atoms or molecules) there are in one mole of a substance. Moles are the fundamental units for chemical equations, such as "Na + 1/2 Cl₂ -> NaCl" which means that one mole of sodium (Na) reacts with one-half mole of chlorine (Cl₂) to produce one mole of sodium chloride (table salt, NaCl). My tie celebrates the periodic table and all sorts of chemistry lab equipment.

28 February 23

Today's chemistry tie celebrates the birthday of Linus Pauling (1901-1994), often regarded as "the Father of the Chemical Bond." In the 1920s and 1930s his research led to understandings of molecular bonding that continue to the present. For his scientific work, Pauling was awarded the Nobel Prize in Chemistry in 1954. In 1962, for his peace activism, he was awarded the Nobel Peace Prize. This makes him the only person to be awarded two unshared Nobel Prizes. I'm also wearing my tie bar that says "Walkabout Expert" because I'm going to show our five-month old graddaughter around her own house today!

28 June 22

Richard August Carl Emil Erlenmeyer was born on this date in 1825. As an early synthetic organic chemist, Emil Erlenmeyer was known for his work with aliphatic hydrocarbons and the chemistry of fermentation. He worked with Robert Bunsen and August Kekulé. Around 1857 he designed a glass conical flask with tapered neck, angled sides and a flat bottom, features which proved exceptionally useful for titrations and also when recrystallizing the products of chemical reactions. By 1861 the Erlenmeyer flask was becoming a standard piece of laboratory glassware. Among my chemistry ties this is the only one featuring an Erlenmeyer flask! I'm including an image of Erlenmeyer's own sketch for the flask.

19 April 22

Today's periodic table tie celebrates two events in the history of chemistry. Glenn Seaborg, discoverer of plutonium and other transuranium elements, was born on 19 April 1912 (and died in 1999). Pierre and Marie Curie first purified radium on 20 April 1902. On my tie, the squares for elements 104-106 are labeled "Unq," "Unp" and "Unh," from the names unnilquadium, unnilpentium and unnilhexium, which were used until more official names were adopted in 1997. Element 106, "Unh," was named seaborgium to honor Glenn Seaborg! It was the first time an element was named for a living person. Its atomic symbol is now Sg. The elements discovered by Marie and Pierre Curie -- radium (88) and polonium (84) -- and the element named for them -- curium (96) -- are not included on my tie, but they used some of the pictured standard lab equipment in their research.

22-23 October 21

Tomorrow, 10-23, is celebrated annually by chemists worldwide as Mole Day, based on the exponential part of the super-gigantic number 6.02 x 10²³. It's called Avogadro's Number, and it counts the number of "things" in the scientific unit called the mole. The mole concept is needed because atoms and molecules are much too tiny to be counted in dozens or thousands. One heaping tablespoon of water contains 602,000,000,000,000,000,000,000 molecules! And 56 paper clips have that same number of iron atoms. The mole unit has nothing to do with the ground-burrowing mammal, but celebrations of Mole Day feature all sorts of images of the animal. (And I think it's fun to note that Mole Day comes just a few days after International Sloth Day!)

28 June 21

Richard August Carl Emil Erlenmeyer (1825-1909) was born on this date! He was a German chemist who is known principally for designing the flask named for him.

"The slanted sides and narrow neck of this flask allow the contents of the flask to be mixed by swirling, without risk of spillage, making them suitable for titrations by placing it under the buret and adding solvent and the indicator in the Erlenmeyer flask. Such features similarly make the flask suitable for boiling liquids. Hot vapor condenses on the upper section of the Erlenmeyer flask, reducing solvent loss. Erlenmeyer flasks' narrow necks can also support filter funnels." (Wikipedia)

 

20 April 21

On this day in chemistry: 119 years ago (1902), Marie and Pierre Curie first purified radium, element 88. Yesterday in chemistry: 109 years ago (1912), Glenn Seaborg was born. He became famous for the discovery or co-discovery of ten "transuranic" elements (those with atomic numbers above 92), from plutonium through nobelium and "106" which was named seaborgium in his honor. My tie shows traditional chemistry lab equipment such as that used by the Curies. The periodic table in the background does not have boxes for radium or polonium, but it does show element 106, which was originally labeled "Unh" for unnilhexium.

31 March 20

It's Bunsen Burner Day! Robert Wilhelm Bunsen was born on either 30 or 31 March 1811 -- sources reflect some uncertainty. He is most famous for developing the adjustable flame burner that bears his name, but he was also responsible for the discovery of the elements cesium and rubidium, and for big advances in the use of flame spectrometry in analytical chemistry. My tie features the periodic table and a wide range of laboratory equipment, including a Bunsen burner!

20 August 19

Credit for the Periodic Table of Elements usually goes to Dmitri Mendeleev for the table he published in 1869. As far as we can tell he was unaware of some earlier attempts to classify the 56 elements known at that time, particularly the publication by John Newlands on 20 August 1864. Newlands' chart was based on what he called the "Law of Octaves," recognizing a pattern of similar properties for every eighth element when they were arranged in order of atomic weight. So John Newlands deserves credit for originating the "law of periodicity" so well expressed by the full Periodic Table.

7-8 February 18

On 7 February 1863, English chemist John Newlands published one of the first table of elements, which divided the known 56 elements into 11 groups based on the "Law of Octaves." This suggested that any one element will have similar properties to elements eight places before and behind it on the table. (Source -- National Day Calendar.) This was six years before Dmitri Mendeleev published his more systematic table which became the foundation for what we use today. Mendeleev was born on 8 February 1834, so these two days are special times to honor the periodic table of the elements!

28 June 17

Richard August Carl Emil Erlenmeyer was born on this date in 1825. As an early synthetic organic chemist, Emil Erlenmeyer was known for his work with aliphatic hydrocarbons and the chemistry of fermentation. He worked with Robert Bunsen and August Kekulé. Around 1857 he designed a glass conical flask with tapered neck, angled sides and a flat bottom, features which proved exceptionally useful for titrations and also when "recrystallizing" the products of chemical reactions. By 1861 the Erlenmeyer flask was becoming a standard piece of laboratory glassware. Among my chemistry ties this is the only one featuring an Erlenmeyer flask! I'm including an image of Erlenmeyer's own sketch for the flask.

19 April 17

Some of the entries from the periodic table on this tie are now obsolete, but I will continue wearing it! Element number 106 is called seaborgium, named for the American nuclear chemist Glenn Seaborg, who was born on this date in 1912. On my tie its box is labeled Unh, for the placeholder name "unnilhexium" (meaning one hundred six), which was used from the element's discovery in 1974 until its official naming in 1997. The periodic table hanging on my wall, dating from 1983, includes an empty box for #106 (just below tungsten, #74). Glenn Seaborg was a master pioneer of the nuclear chemistry programs in the mid-twentieth century, the principal or co-discoverer of ten elements: plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium and seaborgium.

28 June 16

Richard August Carl Emil Erlenmeyer was born on this date in 1825. As an early synthetic organic chemist, Emil Erlenmeyer was known for his work with aliphatic hydrocarbons and the chemistry of fermentation. He worked with Robert Bunsen and August Kekulé. Around 1857 he designed a glass conical flask with tapered neck, angled sides and a flat bottom, features which proved exceptionally useful for titrations and also when "recrystallizing" the products of chemical reactions. By 1861 the Erlenmeyer flask was becoming a standard piece of laboratory glassware. Among my chemistry ties this is the only one featuring an Erlenmeyer flask!



This is Erlenmeyer's original sketch:

8 February 16

Two days in a row for the Periodic Table! Dmitri Mendeleev was born on this date in 1834. I wore my "K" tie tack next to the square for potassium. Other things to note about today include the math of 2 X 8 = 16, and the fact that we are currently in "Just Say No to PowerPoint Week."

22-23 October 15

Tomorrow, 10-23, marks the annual celebration of Mole Day, by chemists and their friends worldwide. The number 6.022 X 10**23 counts the number of things (atoms, molecules, paper clips, pianos, whatever) in "one mole" of them. In plain English that number is 602.3 sextillion. The mole is the simplest way to compare amounts of reacting substances. One mole of carbon atoms (C), weighing 12 grams, reacts with one mole of oxygen molecules (O₂), weighing 32 grams, to create one mole of carbon dioxide (CO₂), weighing 44 grams. In the photo I am holding 1 mole (342 grams) of sucrose (C₁₂H₂₂O₁₁) and one mole (18 grams) of water (H₂0); I added a few hundred quadrillion molecules of blue food coloring (in one "tiny drop") to the water for visibility.

8 February 15

Dmitri Mendeleev was born on 8 February 1834. He is most famous for devising the original periodic table of elements, recognizing patterns in the combining weights (now called atomic masses) of chemical elements with similar chemical properties. His table accurately predicted the properties of several elements unknown at the time.

31 March 14

Happy Birthday, Dr. Bunsen! Robert Wilhelm Bunsen was born on this date in 1811. His work in chemistry focused on the spectra (light emissions) from heated elements, and by 1855 he and his lab assistants had perfected the natural-gas burner now named for him.

7 February 13

Tomorrow, Feb. 8, is the birthday of Dmitri Mendeleev (1834-1907), inventor of the periodic table of the elements.

12 September 12

Today's birthday person is Irene Joliot-Curie, born in 1897 to Pierre and Marie Curie. She became a famous chemist in her own right, winning the 1935 Nobel Prize in Chemistry (along with her husband) for her research in radioactivity.