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प्रश्न
When phenolphthalein is added to NaOH, the colour of the solution will become _________.
- colourless
- red
- pink
- yellow
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उत्तर
pink
When phenolphthalein is added to NaOH, the colour of the solution will become pink
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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.
When acids react with metal, which gas is liberated?
Dry HCl gas does not change the colour of dry blue litmus paper. Why?
How is the concentration of hydroxide ions (OH−) affected when excess base is dissolved in a solution of sodium hydroxide?
On adding dilute hydrochloric acid to copper oxide powder, the solution formed is blue-green.
- Predict the new compound formed which imparts a blue-green colour to solution.
- Write a balanced chemical equation of the reaction which takes place.
- On the basis of the above reaction, what can you say about the nature of copper oxide?
What ions are present in the solution of the following substance? (write the symbols only)
Sulphuric acid
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- Name X and Y.
- Write the chemical equation of the reaction of metal X with
- hydrochloric acid, and
- sodium hydroxide solution.
What would be the colour of litmus in a solution of sodium carbonate?
With which substance should chlorine be treated to get bleaching powder?
What are esters? How are esters prepared? Write the chemical equation for the reaction involved. What happens when an ester reacts with sodium hydroxide? Write the chemical equation for the reaction and also state the name and use of this reaction.
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Phenolphthalein is ___________ type of indicator.
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Egg shell is made up of ____________.
Common salt besides being used in kitchen can also be used as the raw material for making
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Which of the following statements is true for acids?
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- In place of zinc granules, same amount of zinc dust is taken in the test tube
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Acids present in fruits and vegetables are called ______ acids.
The taste of acid is ______.
The metal that will not produce hydrogen gas when reacted with dilute acids.
