Syringa is a genus of 12 currently recognized species of flowering woody plants in the olive family or Oleaceae called lilacs. These lilacs are native to woodland and scrub from southeastern Europe to eastern Asia, and widely and commonly cultivated in temperate areas elsewhere.
The genus is most closely related to Ligustrum (privet), classified with it in Oleaceae tribus Oleeae subtribus Ligustrinae.
Asterids are a large clade (monophyletic group) of flowering plants, composed of 17 orders and more than 80,000 species, about a third of the total flowering plant species. The asterids are divided into the unranked clades lamiids (8 orders) and campanulids (7 orders), and the single orders Cornales and Ericales. Well-known asterids include dogwoods and hydrangeas (order Cornales), tea, blueberries, cranberries, kiwifruit, Brazil nuts, argan, sapote, and azaleas (order Ericales), sunflowers, lettuce, common daisy, yacon, carrots, celery, parsley, parsnips, ginseng, ivies, holly, honeysuckle, elder, and valerian (clade campanulids), borage, forget-me-nots, comfrey, coffee, frangipani, gentian, pong-pong, oleander, periwinkle, basil, mint, rosemary, sage, oregano, thyme, lavender, wild dagga, olives, ash, teak, foxgloves, lilac, jasmine, snapdragons, African violets, butterfly bushes, sesame, psyllium, potatoes, eggplants, tomatoes, chilli peppers, tobacco, petunias, morning glory, and sweet potato (clade lamiids).
Most of the taxa belonging to this clade had been referred to as Asteridae in the Cronquist system (1981) and as Sympetalae in earlier systems. The name asterids (not necessarily capitalised) resembles the earlier botanical name but is intended to be the name of a clade rather than a formal ranked name, in the sense of the ICBN.
Potassium is a chemical element; it has symbol K (from Neo-Latin kalium) and atomic number 19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, which is easily removed to create an ion with a positive charge (which combines with anions to form salts). In nature, potassium occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac-colored flame. It is found dissolved in seawater (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a common constituent of granites and other igneous rocks.
Potassium is chemically very similar to sodium, the previous element in group 1 of the periodic table. They have a similar first ionization energy, which allows for each atom to give up its sole outer electron. It was first suggested in 1702 that they were distinct elements that combine with the same anions to make similar salts, which was demonstrated in 1807 when elemental potassium was first isolated via electrolysis. Naturally occurring potassium is composed of three isotopes, of which
K is radioactive. Traces of
K are found in all potassium, and it is the most common radioisotope in the human body.
The Lamiales (also known as the mint order) are an order of flowering plants in the asterids clade of the Eudicots. Under the APG IV system of flowering plant classification the order consists of 24 families, and includes about 23,810 species and 1,059 genera with representatives found all over the world. Well-known or economically important members of this order include aromatic, culinary, and medicinal herbs such as basil, mint, rosemary, sage, savory, marjoram, oregano, hyssop, thyme, lavender, perilla, lemon verbena, catnip, bee balm, wild dagga, and oriental motherwort, as well as olives, ash trees, teak, foxgloves, lilacs, jasmine, snapdragons, African violets, Jacarandas, Paulownias, butterfly bushes, sesame, and psyllium.