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Which indicator is yellow in a solution with a pH of 9.8?

(1) methyl orange (3) bromcresol green
(2) bromthymol blue (4) thymol blue

2 Answers

5 votes
It's the Methyl Orange.
at about 4.4 pH, it changes from red to Yellow, to indicate an acid solution.
This pH indicator is normally used in titration of acids.

Hope this Helps :)
User Rocketmagnet
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2 votes

Answer:

1) Methyl orange

Step-by-step explanation:

Acid base indicators are solutions of certain dyes that bring about a color change at a certain pH i.e. the at a particular H+ ion concentration.

The color change and the pH range for the four indicators mentioned in the question are as follows:

indicator pH range color change

1. Methyl orange 3.2-4.4 red-yellow

2. Bromothymol blue 6.0-7.6 yellow-blue

3. Bromocresol green 3.8-5.4 yellow-green

4. Thymol blue 8.0-9.6 yellow-blue

Based on the above data, only methyl orange is yellow at pH above 4.4. Hence, indicator is yellow in a solution with a pH of 9.8 is methyl orange

User Boxofrats
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