Red-figure potteryRed-figure vase painting is one of the most important styles of figural Greek vase painting. It developed in Athens around 520 BCE and remained in use until the late 3rd century BCE. It replaced the previously dominant style of black-figure vase painting within a few decades. Its modern name is based on the figural depictions in red color on a black background, in contrast to the preceding black-figure style with black figures on a red background. The most important areas of production, apart from Attica, were in Southern Italy.
Black-figure potteryBlack-figure pottery painting, also known as the black-figure style or black-figure ceramic (), is one of the styles of painting on antique Greek vases. It was especially common between the 7th and 5th centuries BCE, although there are specimens dating as late as the 2nd century BCE. Stylistically it can be distinguished from the preceding orientalizing period and the subsequent red-figure pottery style. Figures and ornaments were painted on the body of the vessel using shapes and colors reminiscent of silhouettes.
Sulfur dioxideSulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula SO2. It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of copper extraction and the burning of sulfur-bearing fossil fuels. SO2 is a bent molecule with C2v symmetry point group. A valence bond theory approach considering just s and p orbitals would describe the bonding in terms of resonance between two resonance structures.
Ethylene oxideEthylene oxide is an organic compound with the formula . It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of a silver catalyst.
OzoneOzone (ˈoʊzoʊn) (or trioxygen) is an inorganic molecule with the chemical formula O3. It is a pale blue gas with a distinctively pungent smell. It is an allotrope of oxygen that is much less stable than the diatomic allotrope O2, breaking down in the lower atmosphere to O2 (dioxygen). Ozone is formed from dioxygen by the action of ultraviolet (UV) light and electrical discharges within the Earth's atmosphere. It is present in very low concentrations throughout the latter, with its highest concentration high in the ozone layer of the stratosphere, which absorbs most of the Sun's ultraviolet (UV) radiation.
