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प्रश्न
Answer the following question:
What is the universal indicator? Does Mg (OH)2 react with sodium hydroxide? If not, why?
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उत्तर
- Universal indicator is an indicator which is a mixture of several indicators.
- It has a very wide range and can indicate pH value almost from 0 to 14.
- When one or two drops of the universal indicator are added to a solution, it changes its colour. This colour is matched against the colour on a standard colour chart (usually given on its bottle) to find the pH, and the pH value can be read. This indicates the strength of the solution too.
- Universal indicator is available as a solution or in the form of paper strips.
- Mg(OH)2 does not react with sodium hydroxide as both are bases.
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संबंधित प्रश्न
Dilute NaOH can be tested with
(a) red litmus paper
(b) blue litmus paper
(c) lime water
(d) Na2CO3
| Column A | Column B | ||
| i | eosin | 1 | losing hydrogen |
| ii | oxidation | 2 | synthetic indicator |
| 3 | losing oxygen | ||
| 4 | natural indicator |
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