How Decomposition reaction is used in daily life ?

 Write the products of following chemical reaction:

$2FeS{O}_4.7H_{2}O\stackrel{∆}{\to }M\stackrel{∆}{\to }X+Y+Z$

Consider the following statements:

1. Reactions in which heat is released along with the formation of products are called exothermic chemical reactions.
2. Reactions in which energy is absorbed, are known as endothermic reactions.

Which of the statements given above is/are correct?

Consider the following reactions:

$Z{n}_{\left(s\right)} + CuS{O}_{4\left(aq\right)}\to$
$F{e}_{\left(s\right)}+ ZnS{O}_{4\left(aq\right)}\to$
$Z{n}_{\left(s\right)}+ FeS{O}_{4\left(aq\right)}\to$

Which of the above chemical reaction(s) will take place?

Consider the following reaction:

$CuO + H_2\stackrel{Heat}{\to } Cu + H_{2}O$   

Which species get oxidized in the given chemical reaction?

Sodium and potassium are stored in kerosene. Give reason. The following reasons are given by class VIII students.

1. Both are highly reactive and react with carbon dioxide in the atmosphere.

2. Both are highly toxic and give off toxic fumes.

3. Both are highly reactive and react with oxygen in the atmosphere.

4. Kerosene helps cut off the reaction of the metals with oxygen in the air.

Select the most appropriate reason(s) given by class VIII students.

Select from the following the reactions that is/are possible.

1. $A{l}_2(S{O}_4{)}_{3\left(aq\right)}+C{u}_{\left(s\right)}\to$  

2. $FeS{O}_{4\left(aq\right)}+Z{n}_{\left(s\right)}\to$

3. $CuS{O}_{4\left(aq\right)}+F{e}_{\left(s\right)}\to$

4. $A{l}_2(S{O}_4{)}_{3\left(aq\right)}+Z{n}_{\left(s\right)}\to$

Student (X) has taken five $100 mL$ beakers and labelled them A, B, C, D and E and also added $50 mL$ of water in each beaker. After that, she added the following composition of substance in each beaker. It is as follows:

Beaker A: Copper sulphate $\left(CuS{O}_4\right)$+ Zinc granule $\left(Zn\right)$
Beaker B: Copper sulphate $\left(CuS{O}_4\right)$+ Iron nail $\left(Fe\right)$
Beaker C: Zinc sulphate $\left(ZnS{0}_4\right)$+ Copper turnings $\left(Cu\right)$
Beaker D: Iron sulphate $\left(FeS{0}_4\right)$+ Copper turnings $\left(Cu\right)$
Beaker E: Zinc sulphate $\left(ZnS{0}_4\right)$+ Iron nail $\left(Fe\right)$.

Which of the following concepts is used to study the given reactions?