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Litmus
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. In an acidic medium, blue litmus paper turns red, while in a basic or alkaline medium, red litmus paper turns blue. In short, it is a dye and indicator which is used to place substances on a pH scale. History The word "litmus" comes from the Old Norse word "litmosi" meaning "colour moss" or "colouring moss". The word is attested only in one Mediaeval source, a Norwegian law codex from 1316 in a chapter on customs and excise duties on pelts and furs. About 1300, the Spanish physician Arnaldus de Villa Nova began using litmus to study acids and bases. From the 16th century onwards, the blue dye was extracted from some lichens, especially in the Netherlands. Natural sources Litmus can be found in many different species of lichens. The dyes are extracted from such species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litmus Paper
Litmus is a water-soluble mixture of different dyes extracted from lichens. It is often absorbed onto filter paper to produce one of the oldest forms of pH indicator, used to test materials for acidity. In an acidic medium, blue litmus paper turns red, while in a basic or alkaline medium, red litmus paper turns blue. In short, it is a dye and indicator which is used to place substances on a pH scale. History The word "litmus" comes from the Old Norse word "litmosi" meaning "colour moss" or "colouring moss". The word is attested only in one Mediaeval source, a Norwegian law codex from 1316 in a chapter on customs and excise duties on pelts and furs. About 1300, the Spanish physician Arnaldus de Villa Nova began using litmus to study acids and bases. From the 16th century onwards, the blue dye was extracted from some lichens, especially in the Netherlands. Natural sources Litmus can be found in many different species of lichens. The dyes are extracted from such speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lichens
A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), mutualistic relationship.Introduction to Lichens – An Alliance between Kingdoms . University of California Museum of Paleontology. . Lichens are the lifeform that first brought the term symbiosis (as ''Symbiotismus'') into biological context. Lichens have since been recognized as important actors in nutrient cycling and producers which many higher trophic feeders feed on, such as reindeer, gastropods, nematodes, mites, and springtails. Lichens have properties different from those of their component organisms. They come in man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PH Indicator
A pH indicator is a halochromism, halochromic chemical compound added in small amounts to a Solution (chemistry), solution so the pH (acidity or Base (chemistry), basicity) of the solution can be determined visually or spectroscopically by changes in absorption and/or emission properties. Hence, a pH indicator is a Chemical substance, chemical detector for hydronium ions (H3O+) or hydrogen ions (H+) in the Acid-base reaction theories, Arrhenius model. Normally, the indicator causes the color of the solution to change depending on the pH. Indicators can also show change in other physical properties; for example, olfactory indicators show change in their odor. The pH value of a neutral solution is 7.0 at 25°C (Standard conditions for temperature and pressure#Standard laboratory conditions, standard laboratory conditions). Solutions with a pH value below 7.0 are considered acidic and solutions with pH value above 7.0 are basic. Since most naturally occurring Organic compound, organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basicity
In chemistry, there are three definitions in common use of the word "base": ''Arrhenius bases'', ''Brønsted bases'', and ''Lewis bases''. All definitions agree that bases are substances that react with acids, as originally proposed by Guillaume-François Rouelle, G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form hydroxide ions OH−. These ions can react with Hydron (chemistry), hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. They are slippery to the touch, can taste Taste#Bitterness, bitter and change the color of pH indicators (e.g., turn red litmus paper blue). In water, by altering the self-ionization of water, autoionization Chemical equi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base (chemistry)
In chemistry, there are three definitions in common use of the word "base": '' Arrhenius bases'', '' Brønsted bases'', and '' Lewis bases''. All definitions agree that bases are substances that react with acid An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis ...s, as originally proposed by Guillaume-François Rouelle, G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form hydroxide ions OH−. These ions can react with Hydron (chemistry), hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid (chemistry)
An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the proton donors, or Brønsted–Lowry acids. In the special case of aqueous solutions, proton donors form the hydronium ion H3O+ and are known as Arrhenius acids. Brønsted and Lowry generalized the Arrhenius theory to include non-aqueous solvents. A Brønsted–Lowry or Arrhenius acid usually contains a hydrogen atom bonded to a chemical structure that is still energetically favorable after loss of H+. Aqueous Arrhenius acids have characteristic properties that provide a practical description of an acid. Acids form aqueous solutions with a sour taste, can turn blue litmus red, and react with bases and certain metals (like calcium) to form salts. The word ''acid'' is derived from the Latin , meaning 'sour'. An aqueous solution of an acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acidity
An acid is a molecule or ion capable of either donating a proton (i.e. hydrogen cation, H+), known as a Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the proton donors, or Brønsted–Lowry acids. In the special case of aqueous solutions, proton donors form the hydronium ion H3O+ and are known as Arrhenius acids. Brønsted and Lowry generalized the Arrhenius theory to include non-aqueous solvents. A Brønsted–Lowry or Arrhenius acid usually contains a hydrogen atom bonded to a chemical structure that is still energetically favorable after loss of H+. Aqueous Arrhenius acids have characteristic properties that provide a practical description of an acid. Acids form aqueous solutions with a sour taste, can turn blue litmus red, and react with bases and certain metals (like calcium) to form salts. The word ''acid'' is derived from the Latin , meaning 'sour'. An aqueous solution of an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid
An acid is a molecule or ion capable of either donating a proton (i.e. Hydron, hydrogen cation, H+), known as a Brønsted–Lowry acid–base theory, Brønsted–Lowry acid, or forming a covalent bond with an electron pair, known as a Lewis acid. The first category of acids are the proton donors, or Brønsted–Lowry acid–base theory, Brønsted–Lowry acids. In the special case of aqueous solutions, proton donors form the hydronium ion H3O+ and are known as Acid–base reaction#Arrhenius theory, Arrhenius acids. Johannes Nicolaus Brønsted, Brønsted and Martin Lowry, Lowry generalized the Arrhenius theory to include non-aqueous solvents. A Brønsted–Lowry or Arrhenius acid usually contains a hydrogen atom bonded to a chemical structure that is still energetically favorable after loss of H+. Aqueous Arrhenius acids have characteristic properties that provide a practical description of an acid. Acids form aqueous solutions with a sour taste, can turn blue litmus red, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roccella Tinctoria
''Roccella tinctoria'' is a lichenised species of fungus in the genus '' Roccella'', homotypic synonym of ''Lecanora tinctoria'' (DC.) Czerwiak., 1849. It was first described by Augustin Pyramus de Candolle in 1805. It has the following varieties: * ''R. t.'' var. ''portentosa'' * ''R. t.'' var. ''subpodicellata'' * ''R. t.'' var. ''tinctoria'' and formae: * ''R. t.'' f. ''complanata'' * ''R. t.'' f. ''tinctoria'' Uses It is used to make litmus, a mixture of several organic compounds. Lichen has been used for centuries to make dyes. This includes royal purple colors derived from roccella tinctoria, also known as orseille. The process of making this dye was a secret and lead to the wealth of the weavers of Grainville-la-Teinturière and the Rucellai family of Florence, whose family name is related with the Latin name of the plant, ''oricellum''. There has been speculation that the abundance of roccella tinctoria on the Canary Islands offered a profit motive for Jean de Bét ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parmotrema Tinctorum
''Parmotrema tinctorum'' is a lichen which belongs to the ''Parmotrema ''Parmotrema'' is a genus of lichen belonging to the family Parmeliaceae. It is a large genus, containing an estimated 300 species, with a centre of diversity in subtropical regions of South America and the Pacific Islands. Members of the genus ...'' genus. The lichen is as known as the Palm Ruffle Lichen and is listed as secure by the Nature Conservatory. Description Grows to around 3–30 cm in diameter with board dull smooth slightly shiny gray lobes that are 10–20 mm wide. The underside is black with naked brown areas with a central collection of simple rhizines. Habitat and range Global distribution with a majority of samples being located in North America and Europe. Chemistry Compounds derived from Parmotrema tinctorum have been found to have anti-cancer properties. Environmental monitoring Parmotrema tinctorum has been identified and used as a candidate for monitoring air polluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
