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प्रश्न
From which plant is litmus paper or litmus solution obtained?
- Moss
- Rose
- Hibiscus
- Lichen
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उत्तर
(d) Lichen.
Litmus is a water soluble mixture of different dyes extracted from lichens, especially Roccella tinctoria.
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संबंधित प्रश्न
What do we observe on pouring acetic acid on red and blue litmus papers?
(A) Red litmus remains red and blue litmus turns red.
(B) Red litmus turns blue and blue litmus remains blue.
(C) Red litmus turns blue and blue litmus turns red.
(D) Red litmus becomes colourless and blue litmus remains blue.
How is the concentration of hydronium ions (H3O+) affected when a solution of an acid is diluted?
How is the concentration of hydroxide ions (OH−) affected when excess base is dissolved in a solution of sodium hydroxide?
Equal lengths of magnesium ribbons are taken in test tubes A and B. Hydrochloric acid (HCl) is added to test tube A, while acetic acid (CH3COOH) is added to test tube B. In which test tube will the fizzing occur more vigorously, and why?
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NaOH (aq) HCI (aq)→
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A first-aid manual suggests that vinegar should be used to treat wasp stings and baking soda for bee stings. What does this information tell you about the chemical nature of:
bee stings?
What is the chemical formula of washing soda?
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Choose the correct alternative and rewrite the following sentence.
Phenolphthalein is ___________ type of indicator.
The table given below shows the reaction of a few elements with acids and bases to evolve Hydrogen gas.
| Element | Acid | Base |
| A |
✗
|
✗ |
| B |
✓
|
✓ |
| C | ✓ | ✗ |
| D | ✓ | ✓ |
Which of these elements form amphoteric oxides?
Which of the following salts does not contain any water of crystallisation?
Which of the following gives the correct increasing order of acidic strength?
In the following schematic diagram for the preparation of hydrogen gas as shown in the figure, what would happen if following changes are made?
- In place of zinc granules, same amount of zinc dust is taken in the test tube
- Instead of dilute sulphuric acid, dilute hydrochloric acid is taken
- In place of zinc, copper turnings are taken
- Sodium hydroxide is taken in place of dilute sulphuric acid and the tube is heated.
A salt may be ______.
______ change the colour of the indicators.
What is the correct procedure for mixing acid and water? Why?
