Francium
Francium (), formerly known as eka-caesium and actinium K , is a chemical element that has the symbol Fr and atomic number 87. It has the lowest known electronegativity of all known elements, and is the second rarest naturally occurring element (after as more
History of saffron
fresco from the excavation of Akrotiri on the Aegean island of Santorini .
The history of saffron in human cultivation and use reaches back more than 3,000 years. and spans many cultures, continents, and civilizations. Saffron , a spice derived from the dried stigmas of t more
Cyclol , mainly because it eliminates the resonance stabilization of the peptide bond . This reaction was the basis of Dorothy Wrinch's cyclol model of proteins.
The cyclol hypothesis is the first structural model of a folded , globular protein . The same studies appeared to show that the mo more
Joseph Priestley
(1794)
Joseph Priestley (13 March 1733 (old style ) – February 6 , 1804 ) was an 18th-century British theologian , Dissenting clergyman , natural philosopher , educator, and political theorist who published over 150 works. He is usually credited with the discovery of oxygen more
Hydrogen
Hydrogen (), is the chemical element represented by the symbol H and an atomic number of 1. At standard temperature and pressure it is a colourless, odorless, nonmetal lic, tasteless, highly flammable diatomic gas (H2).
Properties
With an atomic mass of 1.00794 amu, hydrogen is th more