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प्रश्न
Dilute NaOH can be tested with
(a) red litmus paper
(b) blue litmus paper
(c) lime water
(d) Na2CO3
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.
APPEARS IN
संबंधित प्रश्न
From which plant is litmus paper or litmus solution obtained?
- Moss
- Rose
- Hibiscus
- Lichen
When acids react with metal, which gas is liberated?
A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains ______.
Write a word equation and then a balanced equation for the reaction taking place when:
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The litmus paper or the litmus solution is obtained from ________ plant
(A) Moss
(B) Lichen
(C) Rose
(D) Hibiscus
Give chemical equation of the reaction involved.
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Nitric acid
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(A) There is a layer of water over the layer of acetic acid.
(B) A precipitate is setting at the bottom of the test-tube.
(C) Bubbles of colourless gas are coming out of the test-tube.
(D) There is a clear, colourless transparent solutions in the test-tube.
Read the following statements:
I. When a red litmus paper is dipped into reaction mixture of a saponification reaction, it turns blue and the reaction is exothermic.
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.
Which of the above statements are correct:
(A) I, and II
(B) II and III
(C) III and IV
(D) I and IV
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Which acid is present in milk?
Are all acids corrosive in nature? Name a few acids which are non-corrosive and may be part of our food.
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Consider the following salt:
\[\ce{ZCO3}\]
What would be the change in colour in blue litmus if \[\ce{ZCO3}\] is added to it and Z is potassium?
For each of the salt: A, B, C and D, suggest a suitable method of its preparation.
C is a soluble salt of copper.
