Question

1) What is chemical reaction?
2) What is balanced chemical equation? Why should chemical equations be balanced?
3) What is the difference between exothermic and endothermic reaction? Explain with example.
4) What is combination and decomposition reaction? Explain with example.
5) What is displacement and double displacement reaction? Explain with example.
6) What is redox reaction? Give example and identify oxidised and rudeced substance in the reaction.
7) Write short note on :-
a) Corrosion
b) Rancidity
8) How can you prevent any substance from corrosion and rancidity write the methods?

Answer 1

Answer:

1. Chemical Reaction is the process where one or more substances i.e., reactants are converted into one  or more products.
2. A balanced chemical equation consists of equal number of atoms on both reactants and products side. the chemical equation should be balanced because every it should follow law of conservation of mass.

3. In simple, the release of energy during a chemical reaction , it is exothermic and the liberation of energy during a chemical reaction, it is endothermic.     Eg for endothermic : 6CO2 + 6H2O + sunlight = C6H12O6 +6O2   .  Eg for exothermic : Formation of ice from water.

4. combination reaction is a reaction where two or more compounds react to form a new substance. Eg : 2Na+Cl2=2NaCl

   decomposition reaction is a reaction where one single substance breaks down into two or more elements or compounds. Eg : 2MgO=2Mg+O2

5. displacement reaction is a reaction where an element displaces another element of a compound. EG : Zn + H2SO4 = ZnSO4 + H2

double displacement reaction is a reaction where more reactive elements displace less reactive element in its aquous solution.

I dont know the others dude : )