(a) What is an acid-base indicator? Name the three common indicators used in chemistry laboratory.

(b) Name an acid-base indicator extracted from lichen.

(c) What colour does the methyl orange turn to when put in an acidic solution ?

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Solution

a) Acid-base indicators are substances that determines whether a solution is an acid or a base primarily based on change in their characteristic colour or odour.

The three common indicators are:-
i. Litmus paper
ii. Methyl orange
iii. Phenolphthalein

b)Acid base indicator extracted from lichen is Litmus which further processed to make litmus paper.

c) Methyl orange changes its colour from orange to red when added to an acidic solution.

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Similar questions

Q. (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?

Q. Consider the following statements :

(A) Both acids and bases change the colour of all indicators.
(B) If an indicator gives a colour change with an acid, it does not give a change with a base.
(C) If an indicator changes colour with a base, it does not change colour with an acid.
(D) Change of colour in an acid and a base depends on the type of the indicator.

Which of these statements are correct?

Q. An unknown solution turns red when an acid-base indicator is mixed with it. Which of the given options shows the indicator and nature of the solution, respectively?

(A) Phenolphthalein; Acid
(B) Methyl orange; Acid
(C) Methyl orange; Base
(D) Phenolphthalein; Base

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. An indicator imparts a specific colour to an acidic solution and its colour changes. when the solution becomes basic or alkaline. The same applies to the basic solution as well. Will there be a color change if dilute HCl solution is slowly added to the solution of ${Na}_{2} {CO}_{3}$ and few drops of methyl orange?

Q. Name he acid-base indicator extracted from lichens.

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(a) What is an acid-base indicator? Name the three common indicators used in chemistry laboratory. (b) Name an acid-base indicator extracted from lichen. (c) What colour does the methyl orange turn to when put in an acidic solution ?

(a) What is an acid-base indicator? Name the three common indicators used in chemistry laboratory.

(b) Name an acid-base indicator extracted from lichen.

(c) What colour does the methyl orange turn to when put in an acidic solution ?