Johan Gadolin

Johan Gadolin (June 5, 1760 – August 15, 1852) was a Finnish chemist, physicist and mineralogist. Gadolin discovered the chemical element yttrium. He was also the founder of Finnish chemistry research, as the second holder of the Chair of Chemistry, established in 1761 and first held by Pehr Adrian Gadd (April 4, 1727 – August 11, 1797). Portrait of Johan Gadolin (1760–1852). ... Portrait of Johan Gadolin (1760–1852). ... is the 156th day of the year (157th in leap years) in the Gregorian calendar. ... 1760 was a leap year starting on Tuesday (see link for calendar). ... is the 227th day of the year (228th in leap years) in the Gregorian calendar. ... 1852 was a leap year starting on Thursday (see link for calendar). ... A chemist pours from a round-bottom flask. ... Not to be confused with physician, a person who practices medicine. ... Mineralogy is an earth science that involves the chemistry, crystal structure, and physical (including optical) properties of minerals. ... The periodic table of the chemical elements A chemical element, or element, is a type of atom that is defined by its atomic number; that is, by the number of protons in its nucleus. ... General Name, Symbol, Number yttrium, Y, 39 Chemical series transition metals Group, Period, Block 3, 5, d Appearance silvery white Atomic mass 88. ... For other uses, see Chemistry (disambiguation). ...

Early life

Johan Gadolin was born in Turku, Finland. He began to study mathematics at the Royal Academy of Turku when he was fifteen. Soon he found mathematics too laborious and changed his major to chemistry. In 1779 Gadolin moved to Uppsala University where he was taught by Torbern Bergman. Location of Turku in Northern Europe Coordinates: , Country Finland Province Western Finland Region Finland Proper Sub-region Turku sub-region Government  - Mayor Mikko Pukkinen Area  - City 306. ... Euclid, Greek mathematician, 3rd century BC, as imagined by by Raphael in this detail from The School of Athens. ... The Royal Academy of Turku (Sv: Ã…bo Kungliga Akademi), was the name of the University of Helsinki until 1809, when it was renamed. ... Uppsala University (Swedish Uppsala universitet) is a public university in Uppsala, Sweden. ... Torbern Olof Bergman (March 20, 1735 Katrineberg, Sweden, – July 8, 1784 Medevi, Sweden) was a Swedish chemist. ...

Chemistry

Gadolin became famous when he discovered the first rare earth element. In 1792 Gadolin received a sample of black, heavy mineral found in a quarry in the Swedish village Ytterby near Stockholm. By careful experiments, he isolated a rare earth oxide which was later named yttria. He also isolated in the same study yttrium trihydroxide. Yttria, or yttrium oxide, was the first known rare earth metal compound — at that time, it was regarded as an element. The work was published in 1794. Rare earth ore Rare earth elements and rare earth metals are trivial names sometimes applied to a collection of 17 chemical elements in the periodic table, namely scandium, yttrium, and the lanthanides. ... 1792 was a leap year starting on Sunday (see link for calendar). ... A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure and specific physical properties. ... For other uses, see Quarry (disambiguation). ... Vaxholm To meet Wikipedias quality standards, this article or section may require cleanup. ... For other uses, see Stockholm (disambiguation). ... Yttrium oxide is an oxide of yttrium. ... Yttrium oxide is Y2O3. ...

The mineral that Gadolin examined was named gadolinite in 1800. The oxide of the element gadolinium, gadolinia, was named after Gadolin by its discoverers. Gadolinite is a mineral of a nearly black color and vitreous luster, and consisting principally of the silicates of cerium, lanthanum, neodymium, yttrium, beryllium, and iron with formula: (Ce,La,Nd,Y)2FeBe2Si2O10. ... General Name, Symbol, Number gadolinium, Gd, 64 Chemical series lanthanides Group, Period, Block n/a, 6, f Appearance silvery white Standard atomic weight 157. ...

In an earlier paper in 1788 Gadolin showed that the same element can show several oxidation states, in his case Sn(II) and Sn(IV) 'by combining itself with larger or smaller amounts of the calcinating substance'. He vividly described the disproportionation reaction 2 Sn(II) = Sn(0) + Sn(IV). Disproportionation is a concept in chemistry and is a redox reaction where a reactant is both oxidised and reduced in the same chemical reaction. ...

Gadolin also studied specific heats and latent heats in 1787–92. This thermochemical work was very precise. The specific heat capacity (symbol c or s, also called specific heat) of a substance is defined as heat capacity per unit mass. ... In thermochemistry, latent heat is the amount of energy in the form of heat released or absorbed by a substance during evaporation. ...

One of his latest studies was the chemical analysis of the Chinese alloy pak tong (alpacca, German silver) in 1810 and 1827.

Gadolin became the professor of chemistry at the Royal Academy of Åbo in 1797. He was one of the first chemists who gave laboratory exercises to students. He even allowed the students to use his private laboratory. Gadolin wrote the first anti-phlogiston chemistry textbook in the Nordic countries. The phlogiston theory is a now discredited 17th century hypothesis regarding combustion. ... Political map of the Nordic countries and associated territories. ...

External links

• Sir Johan Gadolin of Turku: The Grandfather of Gadolinium