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प्रश्न
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
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उत्तर १
- The preparation of dilute sulphuric acid falls into the category of an extreme exothermic process.
- During the preparation of dilute sulphuric acid, a large amount of water is taken into a glass container that is surrounded by ice. Cool it for twenty minutes. Now a small quantity of conc. H2SO4 is added slowly with stirring. Therefore, only a small amount of heat is liberated at a time. In this way, dilute sulphuric acid is prepared.
- On the other hand, in the process of dilution or conc. sulphuric acid with water, a very large amount of heat is liberated. As a result, water gets evaported instantaneously if it is poured into conc. H2SO4, which may cause an accident.
उत्तर २
- This is an exothermic reaction.
- If we quickly put concentrated sulphuric acid into water. Water evaporates instantly, liberating a tremendous amount of heat that could cause an accident.
- To avoid this, a tiny amount of heat is supplied gently to water while stirring constantly.
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संबंधित प्रश्न
How will you obtain Ammonia from nitrogen.
Also give balanced equations for the reactions
What do you observe when Ammonia is brought in contact of hydrogen chloride.gas.
State the effect of an endothermic reaction.
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
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- Thermal decomposition reactions
- Exothermic reactions
- Endothermic reactions
- None of these
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\[\ce{2KClO_{3(s)}->[\Delta] 2KCl_{(s)} + 3O2}\]
Identify the endothermic and exothermic reaction.
\[\ce{CaCO_{3(s)}->[\Delta] CaO_{(s)} + CO2}\]
Complete the following statement.
On heating, hydrated copper sulphate changes its colour from ________ to __________.
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The element molybdenum used in the reaction of nitrogen with hydrogen at elevated temperatures is an example of a ________.
Give an example with a balanced equation, of the following reaction:
exothermic reaction
Select the correct answer from the options given below:
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Select the correct answer from the options given below:
State the gaseous product formed, when
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Respiration is a ______ change.
Match the following:
| Colum I | Column II | ||
| 1. | Alloying | a. | Exothermic change |
| 2. | Crystallization | b. | Periodic change |
| 3. | Soap powder + water | c. | Mixing of molten solids |
| 4. | Seasonal changes | d. | Pure solid |
Give examples of the endothermic process.
Identify the type of chemical reaction given below:
\[\ce{2KClO3 -> 2KCl + 3O2 ^}\]
Give scientific reasons.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
