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प्रश्न
Define: Endothermic reaction
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उत्तर
The reactions in which heat is absorbed are called endothermic reactions. The reactants absorb heat for form products.
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संबंधित प्रश्न
Why should a magnesium ribbon be cleaned before it is burnt in the air?
Translate the following statement into a chemical equation and then balance it.
Potassium metal reacts with water to give potassium hydroxide and hydrogen gas.
How will you indicate the following effect in a chemical equation?
Exothermic reaction
Balance the following equation:
\[\ce{Mg(OH)2 + HCl -> MgCl2 + H2O}\]
Giving examples, state the difference between balanced and unbalanced chemical equations.
What are the various ways in which a chemical equation can be made more informative? Give examples to illustrate your answer.
Aluminium hydroxide reacts with sulphuric acid to form aluminium sulphate and water. Write a balanced equation for this reaction.
State the various characteristics of chemical reactions.
State one characteristic of the chemical reaction which takes place when quicklime is treated with water
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- Name any two metals which can behave like metal X.
- Name any two acids which can behave like acid Y.
- Name the gas Z.
- Is the gas Z lighter than or heavier than air?
- Is the reaction between metal X and dilute acid Y exothermic or endothermic?
- By taking a specific example of metal X and dilute acid Y, write a balanced chemical equation for the reaction which takes place. Also indicate physical states of all the reactants and products.
A metal X forms a salt XSO4. The salt XSO4 forms a clear solution in water which reacts with sodium hydroxide solution to form a blue precipitate Y. Metal X is used in making electric wires and alloys like brass.
- What do you think metal X could be?
- Write the name, formula and colour of salt XSO4.
- What is the blue precipitate Y?
- Write a chemical equation of the reaction which takes place when salt XSO4 reacts with sodium hydroxide solution. Give the state symbols of all the reactants and products which occur in the above equation.
A white precipitate will be formed if we add common salt solution to ______.
A colourless lead salt, when heated, produces a yellow residue and brown fumes.
- Name the lead salt.
- Name the brown fumes.
- Write a chemical equation of the reaction involved.
Write your observations and name the product when
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FeCI2 + CI2 → FeCI3
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\[\ce{S + HNO3 -> H2SO4 + NO2 + H2O}\]
Balance the following equation:
MnO2 + HCl → MnCl2 + H2O + Cl2
Balance the following equation:
NO2 +H2O → HNO2 + HNO3
Balance the following equation:
H2O + Cl2 → HCl + O2
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Name the fundamental law that is involved in every equation.
Write the balanced chemical equation of the following reaction.
potassium bicarbonate + sulphuric acid → potassium sulphate + carbon dioxide + water
Write the balanced chemical equation of the following reaction.
ammonia + oxygen → nitric oxide + water
Write the balanced chemical equation of the following reaction.
Potassium permanganate + hydrochloric acid → potassium chloride + manganese chloride + chlorine + water
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- Ammonia
- Sulphur dioxide
- Hydrogen Chloride
- Chlorine
- Carbon Dioxide
- Oxygen
- Hydrogen
(b) Select a basic gas mentioned in Q.1 (a). How is the basic nature suspected?
(c)Select acidic gases from the gases mentioned in Q.1 (a). How is the acidic nature suspected?
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(e)Which gas turn blue cobalt chloride paper light pink?
Answer the following question:
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Give word equation for the following chemical reaction and give the names of the product formed.
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Write word equation for the following chemical reaction given below. Also state the observation seen in the case.
\[\ce{2SO2 + O2 ⇌[V2O5][450°C] 2SO3}\]
Balance the following simple equation:
N2 + O2 ⇌ NO
Balance the following simple equation:
NO + O2 → NO2
Balance the following simple equation:
CO2 + C → CO
Match the columns.
| Reactants | Products | Types of chemical reaction | ||
| 1. | MgH2 | → | Mg + H2 | Endothermic |
| 2. | 2H2S + SO2 | → | 3S + 2H2O | Oxidation |
| 3. | CaO + H2O | → | Ca(OH)2 + heat | Exothermic |
| Redox | ||||
A student took a small amount of copper oxide in a conical flask and added dilute hydrochloric acid to it with constant stirring. He observed a change in colour of the solution.
- Write the name of the compound formed and its colour.
- Write a balanced chemical equation for the reaction involved.
