Color reaction

Color reaction

In chemistry, a color reaction or colour reaction is a chemical reaction that is used to transform colorless chemical compounds into colored derivatives which can be detected visually or with the aid of a colorimeter.

The concentration of a colorless solution cannot normally be determined with a colorimeter. The addition of a color reagent leads to a color reaction and the absorbance of the colored product can then be measured with a colorimeter.

A change in absorbance in the ultraviolet range cannot be detected by eye but can be measured by a suitably equipped colorimeter. A special colorimeter is required because standard colorimeters cannot operate below a wavelength of 400 nanometers. It is also necessary to use fused quartz cuvettes because glass is opaque to ultraviolet.

Contents

Color reagents

Many different color reagents have been developed for determining the concentrations of different substances. For example, Nessler's reagent can be used used to determine the concentration of a solution of ammonia.

Thin layer chromatography

In thin layer chromatography (TLC) color reactions are frequently used to detect compound spots by dipping the plate into the reagent or by spraying the reagent onto the plates.

See also

References



Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • color reaction — spalvinė reakcija statusas T sritis fizika atitikmenys: angl. color reaction; colour reaction vok. Farbreaktion, f rus. колориметрическая реакция, f; цветная реакция, f pranc. réaction colorée, f …   Fizikos terminų žodynas

  • color reaction — spalvinė reakcija statusas T sritis chemija apibrėžtis Reakcija, kurios metu kinta spalva. atitikmenys: angl. color reaction; colour reaction rus. цветная реакция …   Chemijos terminų aiškinamasis žodynas

  • solid-phase color reaction — kietafazė spalvinė reakcija statusas T sritis chemija apibrėžtis Spalvinė reakcija, kuriai vykstant spalva keičiasi dėl kietosios fazės atsiradimo ar išnykimo. atitikmenys: angl. solid phase color reaction; solid phase colour reaction; solid… …   Chemijos terminų aiškinamasis žodynas

  • solid-state color reaction — kietafazė spalvinė reakcija statusas T sritis chemija apibrėžtis Spalvinė reakcija, kuriai vykstant spalva keičiasi dėl kietosios fazės atsiradimo ar išnykimo. atitikmenys: angl. solid phase color reaction; solid phase colour reaction; solid… …   Chemijos terminų aiškinamasis žodynas

  • réaction colorée — spalvinė reakcija statusas T sritis fizika atitikmenys: angl. color reaction; colour reaction vok. Farbreaktion, f rus. колориметрическая реакция, f; цветная реакция, f pranc. réaction colorée, f …   Fizikos terminų žodynas

  • Color of the Cross — Theatrical release poster Directed by Jean Claude La Marre Produced by Ken Ha …   Wikipedia

  • reaction — 1. The response of a muscle or other living tissue or organism to a stimulus. 2. The color change effected in litmus and certain other organic pigments by contact with substances such as acids or alkalies; also the property that such substances… …   Medical dictionary

  • Color symbolism and psychology — For the physiological perception of color, see color and color vision. In art and anthropology, color symbolism refers to the use of color as a symbol throughout culture. Color psychology refers to investigating the effect of color on human… …   Wikipedia

  • Reaction to the assassination of John F. Kennedy — John F. Kennedy Around the world, there was a stunned reaction to the assassination of John F. Kennedy, the President of the United States, on November 22, 1963 in Dallas, Texas.[1] The first hour after the shooting, before his death was… …   Wikipedia

  • Réaction de Liebermann — La réaction de Liebermann Burchard est une réaction chimique principalement utilisée comme test révélateur du cholestérol et plus généralement des phénols. Elle a été décrite initialement par Carl Liebermann[1] puis appliquée à la révélation du… …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”