Facts about the Periodic Table
- 19
Radioactive polonium, element 84, was discovered by Marie Curie in 1898 and named after her native Poland, becoming the first element named after a geographic location.
- 18
Tungsten, element 74, has the highest melting point of any element at 3,422 degrees Celsius, making it indispensable for light bulb filaments and high-temperature industrial applications.
- 17
Antimony, element 51, was one of the first elements deliberately isolated by humans around 3000 BCE, making it among the oldest known metallic elements in recorded history.
- 16
Seventeen elements on the Periodic Table were discovered in the 20th century alone, including plutonium in 1940 and einsteinium in 1952.
- 15
Beryllium, element 4, is so toxic that inhaling its dust causes chronic beryllium disease, a debilitating lung condition that has killed numerous industrial workers since the 1940s.
- 14
Gold, element 79, conducts electricity better than any other element except silver, making it essential for circuit boards despite its high cost and rarity.
- 13
Iodine, element 53, sublimates directly from solid to gas at 184 degrees Celsius without passing through a liquid phase, making it visually distinctive when heated.
- 12
Potassium, element 19, reacts so violently with water that it ignites spontaneously at room temperature, burning with a characteristic lilac-colored flame due to potassium's low ionization energy.
- 11
Mercury is the only metal that remains liquid at room temperature, with a melting point of minus 38.83 degrees Celsius and boiling point of 356.73 degrees Celsius on the Periodic Table.
- 10
Ununoctium's official naming in 2016 completed the seventh row of the Periodic Table with all 118 elements having permanent names rather than temporary systematic designations.
- 09
Neon signs glow because neon, element 10, emits a distinctive reddish-orange light when ionized by electrical current, a property unique among noble gases.
- 08
Francium, element 87, exists in such minuscule quantities that fewer than 30 grams exist in Earth's crust at any given moment due to its extreme radioactivity.
- 07
Element 43, technetium, remains the lightest element with no stable isotopes, first synthesized in 1937 by Italian physicists Carlo Perrier and Emilio Segrè.
- 06
Across the Periodic Table, 118 elements exist today, yet scientists estimate only 92 occur naturally on Earth, with the rest created artificially in laboratories.
- 05
Gallium melts at 29.76 degrees Celsius, making it one of only five elements that remain liquid near room temperature on the Periodic Table.
- 04
In 1913, Henry Moseley used X-ray spectroscopy to determine atomic numbers, fundamentally reorganizing the Periodic Table by atomic number rather than atomic weight.
- 03
Helium, element 2, was discovered in the Sun's spectrum in 1868 before being identified on Earth, making it the only element found extraterrestrially first.
- 02
Oganesson, element 118, was officially named in 2016 to honor Russian physicist Yuri Oganessian after its synthesis in 2006.
- 01
Dmitri Mendeleev published the first Periodic Table in 1869 with 63 elements, leaving gaps for undiscovered elements he predicted would exist.