(a) What is an indicator? Name three common indicators.(b) Name the acid-base indicator extracted from lichen.(c) What colour does the turmeric paper turn when put in an alkaline solution? (2024)

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(a) What is an indicator? Name three common indicators.(b) Name the acid-base indicator extracted from lichen.(c) What colour does the turmeric paper turn when put in an alkaline solution? ›

Among all, the common indicators are as follows; litmus

(a) An indicator is a 'dye' that changes colour when it is put in an acid or a base. The three most common indicators are: Litmus, Methyl orange and Phenolphthalein. (b) The acid-base indicator extracted from lichen is Litmus. (c) Turmeric paper turns red when put in an alkaline solution.

Litmus, phenolphthalein and methyl orange are the common acid-base indicators. Basically these are organic dyes with characteristic colours. Litmus is the extract of the plant lichen. Phenolphthalein and methyl orange are synthesised in the laboratory.

Indicators are substances that change colour when they are added to acidic or alkaline solutions. Litmus, phenolphthalein, and methyl orange are all indicators that are commonly used in the laboratory. Change in property is observed when they come in contact with an acidic or basic solution.

Thymol Blue, Phenol Red, and Methyl Orange are all common acid-base indicators. Red cabbage can also be used as an acid-base indicator.

An indicator is used to differentiate between an acidic substance and a basic substance. There is a range of different indicators. Among all, the common indicators are as follows; litmus, china rose, turmeric and phenolphthalein. (b) The acid-base indicator which is extracted from lichen is litmus.

In this report, “hunger” refers to the index based on the four component indicators (undernourishment, child stunt- ing, child wasting, and child mortality). Taken together, the component indicators reflect deficiencies in calories as well as in micronutrients.

Turmeric is an acid base indicator, which changes colour when the solution turns acidic or basic. Turmeric contains a chemical called curcumin, which remains yellow in an acidic or neutral solution, but turns red in a base.

Big 3 combines Taylor's checklists and favorite indicators to create the Big 3 signals. Big 3 stands for Trend, Structure, and Momentum. Criteria that when met can lead to powerful directional moves.

What is the definition of an indicator? ›

An indicator is a measurement or value that gives you an idea of what something is like. ... vital economic indicators, such as inflation, growth and the trade gap. Synonyms: sign, mark, measure, guide More Synonyms of indicator.

Biological indicators or bioindicators are living organisms (microbes, animals and plants) that are used as a potential tool to monitor the changes (either positive or negative) in environmental health and their possible impact on human civilization (Azzazy, 2020).

Some examples of natural indicators are turmeric, grape juice, red cabbage, cherries, onion, beetroot etc. Synthetic indicators are indicators which are synthesized in the laboratory. Examples of synthetic indicators include phenolphthalein, methyl orange etc. litmus paper is also an example of synthetic indicator.

Types of Indicators

Artificial and Natural indicators are the main two types of Chemical indicators. Another type of indicator includes Olfactory indicators. Litmus, red cabbage, turmeric, china rose are a number of the present indicators around us.

Acid-Base Indicator Examples

Litmus is perhaps the best-known pH indicator. Thymol Blue, Phenol Red, and Methyl Orange are all common acid-base indicators. Red cabbage can also be used as an acid-base indicator.

Solution. A purple dye is extracted from a plant called lichen. This dye is called a litmus solution and is commonly used as an indicator.

For example, common indicators such as phenolphthalein, methyl red, and bromothymol blue are used to indicate pH ranges of about 8 to 10, 4.5 to 6, and 6 to 7.5 accordingly. On these ranges, phenolphthalein goes from colorless to pink, methyl red goes from red to yellow, and bromothymol blue goes from yellow to blue.

a A common acid base indicator and a universal indicator: Acid base indicator like litmus tells us only whether a given substance is an acid or a base. Universal indicator gives an idea as to how acidic or basic a substance is. An universal indicator gives different colours with solutions of different p H values.