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Related to litmus: litmus paper


organic dye usually used in the laboratory as an indicator of acidity or alkalinity (see acids and basesacids and bases,
two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Properties
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). Naturally pink in color, it turns blue in alkali solutions and red in acids. Commonly, paper is treated with the coloring matter to form so-called litmus paper. Litmus is extracted, chiefly in the Netherlands, from certain lichens (see archilarchil
or orchil
, blue, red, or purple dye extracted from several species of lichen, also called orchella weeds, found in various parts of the world. Commercial archil is either a powder (called cudbear), a pasty mass (called archil), or a drier paste (called persis).
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), which are mashed, treated with potassium carbonate and ammonia, and allowed to ferment. The resulting product is mixed with various colorless substances, such as chalk or gypsum, and is sold in dark blue lumps, masses, or tablets. The active component of litmus, i.e., the part sensitive to acids or bases, is called erythrolitmin.
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a dye extracted from certain species of lichen (for example, Roccella tinctoria).

The composition of litmus is complex and has not yet been fully established. The pigment component is the weak acid azolitmin, which yields blue salts. Litmus is used as an indicator: it turns red in an acid medium and blue in an alkaline medium. Test papers impregnated with the dye are generally the form used.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


Blue, water-soluble powder from various lichens, especially Variolaria lecanora and V. rocella ; turns red in solutions at pH 4.5, and blue at pH 8.3; used as an acid-base indicator. Also known as lacmus; lichen blue.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


An organic chemical indicator of acidity or alkalinity; is red in color for pH values below 4.5 and blue above 8.3.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.


a soluble powder obtained from certain lichens. It turns red under acid conditions and blue under basic conditions and is used as an indicator
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
References in periodicals archive ?
'We would not be able to address these issues without the expertise of the LITMUS partners and the generosity of the growing number of patients that have agreed to join the Registry.'
Starting as a bootstrap operation, in less than 15 years, the new website also announces the opening of Litmus's second office in Ahmedabad (C, 703, Titanium City Centre, OPP Seema hall, 100 ft road, Satellite, Ahmedabad) and a branch office in Mumbai (1301, B Wing, Rushi heights, Riddhi Garden, Film City Road, Goregaon, Mumbai-400063) besides revealing their ambitious plans of expanding their footprints in Dubai, UK and USA.
Integrating Curated into the Litmus ecosystem will give email marketers a key tool for consistently delivering high-quality content to their subscribers, improving email engagement, and increasing lifetime value, Litmus said.
Since its establishment in 2005, Litmus Consulting has been offering a range of technical and core (soft) skills training solutions to the financial industry.
Clinically significant medical burden, defined by a score of 4 or more on the Cumulative Illness Rating Scale (CIRS), was present in 139 of 264 LiTMUS participants with available CIRS data.
The paper, "When the Destination is Retirement: A Way to Keep Investors' Plans on Track," written by Noelle Fox, senior investment and product analyst at The Principal, is intended to help financial professionals use the litmus test to its fullest capacity.
Litmus Rapid-B is the result of collaborative work on bacteria and virus detection between NCTR and the parent company of Litmus Rapid-B, Litmus LLC.
CAST your mind back to school chemistry lessons using litmus paper to see if a liquid was acidic or alkaline.
Of course, the question also arises at a time when the Catholic right, inside and outside of formal church structures, is increasingly linking Catholic faith to a series of boundary-marking litmus tests.
"The Dongria's campaign became a litmus test of whether a small marginalised tribe could stand up to a multinational company," Jo Woodman, a campaigner with the advocacy group Survival international, said in a statement.
Summary: DUBAI/ABU DHABI: Dubai's state-owned utility kicked off a roadshow on Tuesday to raise up to $3 billion in a litmus test of how Dubai entities will fare in debt markets following the Gulf Arab emirate's refinancing crisis.