General Chemistry

750 years ago

1249

University of Oxford founded

350 years ago
1649

Schroeder describes two methods of preparing metallic arsenic

250 years ago
1749

Charles Wood describes for the first time, in a penetrative manner, the metal platinum
Pierre Joseph Macquer edits "Elémens de Chimie Theorique" with which he broadcast chemistry in the days before Lavoisier

200 years ago
1799

Gilberts Annalen founded
The Royal Institution of Great Britain founded
Joseph Priestley discovers carbon monoxide
Joseph Louis Proust researches the constant composition weights of chemical compounds

150 years ago
1849

Journal of the Chemical Society of London founded
Thomas Graham studies diffusion of liquids
Auguste Bravais researches the inner structure of crystals

100 years ago
1899

Setting up of the International Commission for Atomic Weights
James Dezvar prepares solid hydrogen
Herbert Smith constructs a three beam goniometer for measuring, eg. crystal angles and optical activity of crystals
William J Pope and S Peachey make the first splitting of nitrogen-,sulfur-, tin- and tellurium compounds with their optical active compounds
Ernst Cohen demonstrates the existence of three allotropic forms of the element tin. Up to 20 °C the grey tin is stable, between 20 °C and 170 °C tetragonal tin is stable and above 170 °C up to 232 °C rhombic tin is stable. He also explains the phenomenon tinplaque by which at low temperature white tin transfers into grey tin
Hendrik Willem Bakhuis-Roozeboom and Albert Ladenburg demonstrate, independently of each other, when an inactive separable substance will be a racemic compound or mixture of the inactive compounds
Richard Abegg and Guido BodIänder take the electron affinity as a basis of a systematization of inorganic compounds
Carl Engler and J Weissberg make the first systematization of auto-oxidable compounds on the basis of the individual addition power of molecular oxygen
Johannes Thiele postulates his partial valence theory
André Debierne isolates the new radio-active metal actinium from pitchblende
Marie Curie isolates radiolead from pitchblende and Jules Elster and Han F K Geitel demonstrate the powerful radioactivity of this isotope of the newly discovered element polonium
Ernst Rutherford, Friedrich 0 Giesel and Henri Becquerel distinguish two kinds of radioactive rays: and ß rays

50 years ago
1949

Hans Werner Kuhn extends colour theory by including electron-gas-models