That which indicates the condition of acidity, alkalinity, or the deficiency, excess, or sufficiency of a standard reagent, by causing an appearance, disappearance, or change of color, as in titration or volumetric analysis.

A substance used to indicate the end point of a titration by a change in color.

(1) A substance that gives visible change, usually of color, at a desired point in a chemical reaction. (2) A device that indicates the result of a measurement. (3) A reagent in a test kit.

A compound, such as phenolphthalein, that changes color at the endpoint of a titration.

A substance that undergoes an sharp, easily observable change when conditions in its solutions change. See, for example, acid-base indicator and redox indicator.

Indicator is a substance used to show the presence of a chemical substance or ion by its colour. Acid-base indicators are compounds, such as phenolphtaleine and methyl orange, that change colour reversibly, depending on whether the solution is acidic or basic. Oxidation-reduction indicators are substances that show a reversible colour change between oxidized and reduced forms.

a chemical that changes color with changes in pH

A material which can be used to show the endpoint of a chemical reaction, usually by a color change, or a chemical concentration by a depth or shade of color.

weak organic acid whose conjugate base differers in color; used to indicate the pH of a solution.

(chemistry) a substance that changes color to indicate the presence of some ion or substance; can be used to indicate the completion of a chemical reaction or (in medicine) to test for a particular reaction

a chemical substance that changes color when it comes in contact with another chemical substance

a chemical that changes colour

a dye than changes colour when pH changes

a dye that changes color when the pH of the solution changes

a soluble dye that changes its color noticeably over a fairly short range of pH

a substance or mixture of substances that when added to the solution gives a different colours depending on the pH of the solution

a substance that can determine the presence of an acid or base

a substance that changes color at a certain value of pH (acidity or alkalinity)

a substance that changes color depending on exactly how acidic a solution is

a substance that gives a color change at or near the equivalence point

a substance that undergoes a change in colour when the end-point of a titration is reached

a substance which changes color when it reacts with sodium hydroxide

a substance which changes color when the pH changes

a substance which changes colour, depending on whether it is placed in an acidic solution or a basic solution

a substance, which shows by means of a colour change if a substance is acidic or basic

a symptom that argues for the presence of a medical condition

a weak acid having a different colour than in its base form

a weak acid or base whose conjugate forms have different colors

a weak acid that is coloured and whose colour is different from that of its conjugate base (or vice versa)

A substance that is used to determine how acidic or alkaline a solution is by changing colour. The most common indicator is litmus paper, but others include methyl orange and universal indicator. Ketone : A family of chemicals that are compounds of carbon, hydrogen and oxygen, and containing a carbon atom joined to an oxygen atom with a double bond (C=O). However, this double bond must not be at the end of the molecule, as that chemical would be known as an aldehyde. Latent Heat : The heat that is absorbed by a chemical as it melts, evaporates or boils, or the heat that a chemical gives off when it condenses or freezes.

Species whose presence in the community are reflective of the relative condition of the environment.

a substance which changes colour at a given stage in or as a result of a chemical reaction. Phenolphthalein is commonly used in titrations measuring the acidity of vegetable.

ind-ic-ay-ter A dye that will change colour in acids and alkalis.

In biology, an organism, species, or community, that indicates the presence of certain environmental conditions.

In biology, an organism, species, or community whose characteristics define the presence of specific environmental conditions.

A substance, which by means of a colour change, indicates the presence of another substance.

a device or substance used to show the presence of another substance

( Ecol.). Species or communities which, with reference to a site, indicate generally the presence in it of certain conditions, processes and uses and sometimes specifically the species that would grow in it.

any of a variety of substances used to demonstrate the presence, absence, or concentration of a substance.

A material that changes color or another property as the conditions to which it is exposed are changed. Certain indicators can be used to indicate the presence, absence or concentration of alkali, acid or of other substances.

In biology, any biological entity or processes, or community whose characteristics show the presence of specific environmental conditions. 2. In chemistry, a substance that shows a visible change, usually of color, at a desired point in a chemical reaction. 3.A device that indicates the result of a measurement; e.g. a pressure gauge or a moveable scale.

(Chemical) A chemical material or solution which can be used to show (usually by color change or depth of color) the endpoint of a chemical reaction or chemical concentration.

A substance, which by some visible change, such as a change of color, indicates the condition of a solution as to the presence of free acid, alkali, or other substances. Indicators are employed in volumetric (titrimetric) analysis to indicate the end points of reactions.

a chemical that changes color and is used to mark the end point of a titration.