Chemical reaction supplementary

Q1: why respiration is called an exothermic reaction ? give example.

Ans: in the respiration ,heat is released. So respiration is called an exothermic reaction.

C6 H2 O6 H6o2 = 6Co2 + 6H20+ Heat.

Q2: Decomposition reactions are called  of opposite of combination reaction . Why?

Ans : because combination reaction two reactants combine to form one but in decomposition reactant break down into two. So that's why they are opposite of each other.

Q3: which gas is produced during the decomposition of baking soda?

Ans: carbon dioxide.

Q4: what is chemical formula of common salt ?

Ans: NAcl.

Q5: give one example in which decomposition reaction is carried out by

(A) electricity

Ans: H20 electricity H2 + 02.

(B) Heat

Ans: Caco3 heat Ca0 +C02.

Q6: what is thermal decomposition reactions?

Ans: the decomposition reaction which state place in the presence of heat is called thermal decomposition reaction.

Thermal decomposition reaction for example

Caco3 heat Ca0 + C02.

Q7: what is photo decomposition reaction?

Ans: the decomposition reaction which takes place in the presence of sunlight is called photo decomposition reaction .

For eg: 

2Agcl sunlight 2Ag + Cl2.

Q8: what is electrical decomposition reaction?

Ans: the decomposition reaction which takes place in the presence of electricity is called electrical decomposition.

For eg:

2H20 electricity 2H2+02.

Q9: which reactions are used for black and white photography?

Ans: the photo decomposition reaction of silver chloride is a used in black and white photography.

COMPLETE THE FOLLOWING

1 Caco3 = Cao + CO2

2. 2Mg+ O2 = 2Mgo

3. Fe+ Cuso4 = FeSo4+ Cu

4 FeSo4+ cu= no reaction

5 NaoH + HCl = NaCl + H20

6. Zn+ CuSo4 = ZnSo4+ Cu

7. 2Agcl sunlight 2 Ag + Cl2

1 Combination: a reaction in which two or more reactants add up to form a product.

C+02=C02

2 Decomposition: a reaction in which one element displaces another from a compound and takes it place compound.

Caco3 heat = Caco+C02

3. Displacement: a reaction in which one element displaces another from a compound and take its place and compound.

Fe+CuS04 = Cu+FeS04

4. Neutralization: a reaction in which one an acid reacts with a base to form a salt and water.

HCl+NaoH=NaCl+H20

5. Exothermic reaction: a reaction in which heat is released it is called exothermic reaction .

for example: respiration in animals is an exothermic reaction.

6. Endothermic reaction: the reaction in which heat is absorbed are called endo thermic reaction.

Caco3 heat Cao+C02.

CHAPTER- CHEMICAL REACTION SUPPLEMENTARY

ANMOL

(8THD)

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