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प्रश्न
Dilute NaOH can be tested with
(a) red litmus paper
(b) blue litmus paper
(c) lime water
(d) Na2CO3
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उत्तर
(a) red litmus paper
Sodium hydroxide when dissolved in water undergoes the following
reaction:
NaOH(s) + aqs → Na+(aq) + OH−(aq)
The dissociated OH− ions turn moist red litmus paper blue.
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संबंधित प्रश्न
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- Moss
- Rose
- Hibiscus
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Predict the new compound formed which imparts a blue-green colour to solution.
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II. When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is exothermic.
III. When a red litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.
IV. When a blue litmus paper is dipped into reaction mixture of a saponification reaction, its colour does not change and the reaction is endothermic.
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(B) II and III
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