The Hill system (or Hill notation) is a system of writing empirical chemical formulas, molecular chemical formulas and components of a condensed formula such that the number of carbon atoms in a molecule is indicated first, the number of hydrogen atoms next, and then the number of all other chemical elements subsequently, in alphabetical order of the chemical symbols.
Iodine clock reaction. The iodine clock reaction (STd3) is a classical chemical clock demonstration experiment to display chemical kinetics in action; it was discovered by Hans Heinrich Landolt in 1886. Two colourless solutions are mixed and at first there is no visible reaction.
Iodine pentafluoride is an interhalogen compound with chemical formula IF 5. It is a fluoride of iodine. It is a colorless or yellow liquid with a density of 3.250 g cm â3.It was first synthesized by Henri Moissan in 1891 by burning solid iodine in fluorine gas.This exothermic reaction is still used to produce iodine pentafluoride, although the reaction conditions have been improved.t was first synthesized by Henri Moissan in 1891 by burning solid iodine in fluorine gas. This exothermic reaction is still used to produce iodine pentafluoride, although the reaction conditions have been improved.