Monthly Archives: December 2017

Martin Heinrich Klaproth — January 1 marks the start of the new year, but the end of Martin Klaproth. Klaproth was a German apothecary and chemist who discovered the elements uranium, zirconium, and cerium. He also named the elements tellurium and titanium. Klaproth thought he was the discoverer of titanium in an ore of rutile in 1791 but […]

Today In Science History – January 1 – Martin Klaproth

This entry was posted on December 31, 2017 by Todd Helmenstine (updated on August 19, 2025)

Human Skeleton Wordsearch — This Human Skeleton Bones wordsearch is a fun way to identify major bones of the human body. The puzzle is optimized to fit on a standard 8.5″x11″ sheet of paper. Download links: [Wordsearch Image] [Wordsearch PDF] If you need a little help finding one or all of the metals, a […]

Human Skeleton Bones Wordsearch Puzzle

This entry was posted on December 31, 2017 by Todd Helmenstine (updated on April 6, 2024)

Robert Boyle — December 31 marks the passing of Robert Boyle. Boyle was an Irish chemist who made a significant contribution away from the alchemical idea of Aristotle’s four elements to the atomic model of elements. He argued elements consisted of ‘corpuscles’ (atoms) instead of the four traditional elements of earth, air, fire, […]

Today in Science History – December 31 – Robert Boyle

This entry was posted on December 30, 2017 by Todd Helmenstine (updated on June 18, 2025)

Rita Levi-Montalcini — December 30 marks the passing of Rita Levi-Montalcini. Levi-Montalcini was an Italian neurologist who made several discoveries of how cells divide and form new cells with different functionality. Levi-Montalcini began her career in science wanting to be a doctor. She graduated with an M.D. from the University of Turin in […]

Today in Science History – December 30 – Rita Levi-Montalcini

This entry was posted on December 29, 2017 by Todd Helmenstine (updated on May 16, 2021)

Charles Goodyear — December 29 is the birthday of the man who discovered the process to vulcanize rubber. Rubber is a natural polymer collected from trees in India, Malaysia, and Indonesia. The latex sap is collected and refined for commercial use. Rubber was great for applications such as waterproofing and insulation, but it […]

Today in Science History – December 29 – Charles Goodyear

This entry was posted on December 28, 2017 by Todd Helmenstine (updated on January 22, 2023)

Constellations Wordsearch Puzzle — Constellations are patterns we’ve assigned to groups of stars in the night sky. A constellations wordsearch is patterns of letters hidden in a sky of letters. Find the names of major constellations in this wordsearch puzzle. The names of the constellations can be found vertically, horizontally, and diagonally. The puzzle is […]

Constellations Wordsearch Puzzle

This entry was posted on December 28, 2017 by Todd Helmenstine (updated on May 16, 2021)

Metals Wordsearch - Solved — Wordsearch puzzles are a fun way to introduce glossary terms of a subject. This metals wordsearch contains 24 different metals. Each metal could be found vertically, horizontally, or diagonally. The puzzle is optimized to fit on a standard 8.5″x11″ sheet of paper. Download links: [Metals Wordsearch Image] [Metals Wordsearch PDF] […]

Metals Wordsearch Puzzle

This entry was posted on December 27, 2017 by Todd Helmenstine (updated on May 16, 2021)

Tapputi-Belatekallim, a female chemist and perfume maker, is mentioned on a Mesopotamian tablet from around 1200 B.C.E. — The first known chemist was a woman. A Mesopotamian cuneiform tablet from the second millennium B.C. describes Tapputi, a perfumer and palace overseer who distilled the essences of flowers and other aromatic materials, filtered them, added water and returned them to the still several times until she got just what she […]

Who Was the First Chemist? A Woman Named Tapputi

This entry was posted on December 27, 2017 by Anne Helmenstine (updated on May 2, 2026)

Toothpaste isn't the only everyday source of fluoride. (Photo Mix) — If you’re looking to reduce your intake of fluorine and fluoride (one is the element, one is the ion), it may help you to know what everyday products contain them and what steps you can take to limit your exposure:

How to Reduce Fluoride Exposure

This entry was posted on December 27, 2017 by Anne Helmenstine (updated on May 2, 2026)