What is the structure of murexide?
Murexide
| PubChem CID | 18275 |
|---|---|
| Structure | Find Similar Structures |
| Molecular Formula | C8H8N6O6 |
| Synonyms | Murexide UNII-4W6L62S876 Murexide (C.I. 56085) 4W6L62S876 Murexid More… |
| Molecular Weight | 284.19 |
Is murexide an indicator?
Murexide is a metal indicator for Ca, Co, Cu, Ni, Th, and rare earth metals; it is also a colorimetric reagent for calcium and rare earth metals. Murexide is slightly soluble in water, alcohol, and ether. Murexide is unstable in aqueous solution.
What is the indicator in calcium complexometric titration?
Eriochrome Black T
A blue dye called Eriochrome Black T (ErioT) is used as the indicator.
Why murexide is used in determination of calcium?
Murexide, also known as ammonium purpurate or MX, is the ammonium salt of purpuric acid. This metallochromic indicator undergoes a color change in the presence of calcium. A similar behavior characterizes the azo dyes, that contain nitrogen in the form of an azo group (−N=N−) as part of their molecular structure.
Which indicators are used in complexometric titration?
To carry out metal cation titrations using EDTA, it is almost always necessary to use a complexometric indicator to determine when the end point has been reached. Common indicators are organic dyes such as Fast Sulphon Black, Eriochrome Black T, Eriochrome Red B, Patton Reeder, or Murexide.
How do you make a murexide indicator?
1) Murexide (ammonium purpurate) indicator: This indicator changes from pink to purple at the end point. Prepare by dissolving 150 mg dye in 100 g absolute ethylene glycol. Water solutions of the dye are not stable for longer than 1 d.
Why Murexide is used in determination of calcium?
What is the use of murexide indicator?
Murexide is used in analytical chemistry as a complexometric indicator for complexometric titrations, most often of calcium ions, but also for Cu, Ni, Co, Th and rare earth metals. Cf. Eriochrome Black T. Due to the minute amounts needed for this purpose, it is often used in a 1:250 mixture with potassium sulfate.
What is the formula for murexide?
Murexide (NH 4C 8H 4N 5O 6, or C 8H 5N 5O 6·NH 3), also called ammonium purpurate or MX, is the ammonium salt of purpuric acid.
What is the maximum absorbance of murexide?
Murexide is also used as a colorimetric reagent for measurement of calcium and rare-earth metals; for calcium, the pH required is 11.3, detection range lies between 0.2 and 1.2 ppm, and the maximum absorbance wavelength is 506 nm. [citation needed]
How do you make aqueous solution of murexide?
Aqueous solution are yellow at low pH, reddish-purple in weakly acidic solutions, and blue-purple in alkaline solutions. Murexide is prepared by treating alloxantin with ammonia to 100 °C, or by treating uramil (5-aminobarbituric acid) with mercury oxide. It may also be prepared by digesting alloxan with alcoholic ammonia.