The discovery of isomerism.

definition In chemical nomenclature, isomers are molecules that share the same molecular formulae but don’t always share the same properties because of the different arrangement of atoms. DISCOVERY Isomerism was discovered in 1827 when the German chemist Friedrich Wöhler prepared silver cyanate and found out that it had the same formula as silver fulminate; which …

The discovery of isomerism. Read More »

The discovery of nucleic acids.

definition Nucleic acids are one of the four major biomolecules that include carbohydrates, lipids and proteins. DISCOVERY In 1869, the Swiss physician and biologist Johannes Friedrich Miescher discovered nucleic acids when he isolated them from the nuclei of white blood cells. First, he collected pus from used bandages in hospitals. As pus is full of …

The discovery of nucleic acids. Read More »

Infrared radiation

DEFINITION Infrared radiation is electromagnetic radiation having a wavelength in the range from circa 75 x 10⁻⁶ cm to circa 100,000 x 10⁻⁶ cm (0.000075-0.1 cm). Infrared rays thus occupy that part of the electromagnetic spectrum with a frequency less than that of visible light and greater than that of most radio waves, although there is some …

Infrared radiation Read More »

The discovery of incandescence.

definition When an electric current passes through and heats a thin wire (filament) to a very high temperature, the filament becomes incandescent (emits its own light). DISCOVERY Incandescence was demonstrated and reported by the American scientist Ebenezer Kinnersley in 1761. DISCOVERER Here is a painting of Ebenezer Kinnersley: [ux_image id=”422″ width=”50″]

The discovery of cholesterol.

definition Cholesterol is a steroid alcohol found in animal fats and oils, bile, blood, brain tissue, milk, egg yolk, myelin sheaths of nerve fibres, liver, kidneys and adrenal glands. DISCOVERY In 1769, the French chemist François Poulletier de la Salle first isolated cholesterol from gallstones by employing the following method…¹ ³ First, gallstones were powdered and …

The discovery of cholesterol. Read More »