Advertisements
Advertisements
Question
Define: Endothermic reaction
Advertisements
Solution
The reactions in which heat is absorbed are called endothermic reactions. The reactants absorb heat for form products.
APPEARS IN
RELATED QUESTIONS
What is a balanced chemical equation? Why should a chemical equation be balanced?
Balance the following chemical equation.
\[\ce{NaCl + AgNO3 -> AgCl + NaNO3}\]
Find the odd man out:
Turmeric, Methyl Orange, Rose petals, Beetroot.
Write a complete balanced equation for the following reaction:
\[\ce{Sulphur dioxide (gas) + Oxygen (gas) -> Sulphur trioxide (gas)}\]
Balance the following equation:
\[\ce{Fe + O2 -> Fe2O3}\]
Balance the following equation:
\[\ce{HNO3 + Ca(OH)2 -> Ca(NO3)2 + H2O}\]
Aluminium burns in chlorine to form aluminium chloride (AlCl3). Write a balanced chemical equation for this reaction.
With the help of an appropriate example, justify that some of the chemical reactions are determined by the evolution of a gas.
Give a chemical equation for the reaction involved in the above case.
Give one example of a chemical reaction characterised by a change in state.
What do you understand by endothermic reactions?
Give one example of an endothermic reaction.
One of the following is an exothermic reaction. This is:
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.
When a mixture of gases X and Y is compressed to 300 atm pressure and then passed over a catalyst consisting of a mixture of zinc oxide and chromium oxide (heated to a temperature of 300°C), then an organic compound Z having the molecular formula CH4O is formed. X is a highly poisonous gas which is formed in appreciable amounts when a fuel burns in a limited supply of air; Y is a gas which can be made by the action of a dilute acid on an active metal; and Z is a liquid organic compound which can react with sodium metal to produce hydrogen gas.
- What are X, Y and Z?
- Write a balanced chemical equation of the reaction which takes place when X and Y combine to form Z. Indicate the conditions under which the reaction occurs.
Balance the following chemical equation:
\[\ce{Pb(NO3)2_{(s)} ->[Heat] PbO_{(s)} + NO2_{(g)} + O2_{(g)}}\]
Express the following facts in the form of a balanced chemical equation:
“When a strip of copper metal is placed in a solution of silver nitrate, metallic silver is precipitated and a solution containing copper nitrate is formed”.
Write your observation for the following chemical reaction and name the product formed :
When water is added to quick lime?
Write symbolic representation for the following word equation and balance them :
Calcium oxide + Water → Calcium hydroxide
Write symbolic representation for the following word equation and balance them :
Iron + Sulphur → Iron sulphide.
Balance the following equation. Also name the products formed.
`"Mg" + "O"_2 → "MgO"`
Balance the following equation. Also name the product formed.
N2 + H2 → NH3
Balance the following equation. Also name the product formed.
PbCO3 → PbO +CO2
Balance the following equation:
Ca + N2 → Ca3N2
Balance the following equation:
Zn + KOH → K2ZnO2 + H2
Balance the following equation:
C + H2SO4 → CO2 + H2O + SO2
Why should an equation be balanced? Explain with the help of a simple equation.
Write the balanced chemical equation of the following reaction.
copper + nitric acid → copper nitrate + nitric oxide + water
Write the balanced chemical equation of the following reaction.
potassium dichromate + sulphuric acid → potassium sulphate + chromium sulphate + water + oxygen.
The chemical reactions in which heat is liberated are called endothermic reactions.
Write word equation for the following molecular equation:
Na2SO3 + 2HCl [dil.] → 2NaCl + H2O + SO2 [g]
Give word equation for the following chemical reaction and give the names of the product formed.
NH3 + HCl→ NH4Cl
What is meant by ‘reactants’ and ‘products’ in a chemical equation?
Balance the following simple equation:
Mg + N2 → Mg3N2
Balance the following simple equation:
SO2 + O2 ⇌ SO3
Write a balanced equation for the following word equation:
Potassium nitrate → Potassium nitrite + Oxygen
Underline the compound in the equation given below, it is incorrectly balanced and write the correct balancing for the same.
Na2SO3 + HCl → 2NaCl + H2O + SO2
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 | ||||
Which of the following are exothermic processes?
- Reaction of water with quick lime
- Dilution of an acid
- Evaporation of water
- Sublimation of camphor (crystals)
