Answer
418.2k+ views
Hint: The physical change is one in which the identity of atoms in a molecule is the same while in chemical change the atoms lose their initial identity and gain a new identity. In rusting of iron, the iron gets oxidised to form iron oxides.
Complete answer :
First, let us see what are physical and chemical changes.
As we have studied the physical change is the one in which the chemical identity of a substance is constant. It does not change. The chemical change is the one in which the identity of elements is different before the change happened and after the change. The number of atoms of an element may remain the same but their bonding and their identity with respect to molecules get changed. Now, let us see what is rusting. The rust is the common term used for corrosion of iron. The rust is an oxide of iron formed when the iron reacts with oxygen and water. We see that anything made of iron gets corroded when exposed to the outer surface. This is because of oxidation of iron. The process is called rusting. In the outer atmosphere, the oxygen comes from the air and water from the moisture present in the surrounding atmosphere.
The surface of iron once corroded can not get back to its original form. So, it is a chemical change.
Thus, the correct answer is the option a.).
Note: The reactions involved during rusting of iron can be given as -
$Fe \to F{e^{2 + }} + 2{e^ - }$
$4F{e^{2 + }} + {O_2} \to 4F{e^{3 + }} + 2{O^{2 - }}$
$F{e^{2 + }} + 2{H_2}O \rightleftharpoons Fe{(OH)_2} + 2{H^ + }$
Rust results in degradation of iron and iron based structures. To prevent corrosion, the iron is galvanised. In this, a layer of other metal is coated on iron to protect iron from oxidation.
Complete answer :
First, let us see what are physical and chemical changes.
As we have studied the physical change is the one in which the chemical identity of a substance is constant. It does not change. The chemical change is the one in which the identity of elements is different before the change happened and after the change. The number of atoms of an element may remain the same but their bonding and their identity with respect to molecules get changed. Now, let us see what is rusting. The rust is the common term used for corrosion of iron. The rust is an oxide of iron formed when the iron reacts with oxygen and water. We see that anything made of iron gets corroded when exposed to the outer surface. This is because of oxidation of iron. The process is called rusting. In the outer atmosphere, the oxygen comes from the air and water from the moisture present in the surrounding atmosphere.
The surface of iron once corroded can not get back to its original form. So, it is a chemical change.
Thus, the correct answer is the option a.).
Note: The reactions involved during rusting of iron can be given as -
$Fe \to F{e^{2 + }} + 2{e^ - }$
$4F{e^{2 + }} + {O_2} \to 4F{e^{3 + }} + 2{O^{2 - }}$
$F{e^{2 + }} + 2{H_2}O \rightleftharpoons Fe{(OH)_2} + 2{H^ + }$
Rust results in degradation of iron and iron based structures. To prevent corrosion, the iron is galvanised. In this, a layer of other metal is coated on iron to protect iron from oxidation.
Recently Updated Pages
Mark and label the given geoinformation on the outline class 11 social science CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
When people say No pun intended what does that mea class 8 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Name the states which share their boundary with Indias class 9 social science CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Give an account of the Northern Plains of India class 9 social science CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Change the following sentences into negative and interrogative class 10 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Advantages and disadvantages of science
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Trending doubts
Bimbisara was the founder of dynasty A Nanda B Haryanka class 6 social science CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Which are the Top 10 Largest Countries of the World?
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Difference between Prokaryotic cell and Eukaryotic class 11 biology CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Differentiate between homogeneous and heterogeneous class 12 chemistry CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
10 examples of evaporation in daily life with explanations
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Fill the blanks with the suitable prepositions 1 The class 9 english CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Give 10 examples for herbs , shrubs , climbers , creepers
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
How do you graph the function fx 4x class 9 maths CBSE
![arrow-right](/cdn/images/seo-templates/arrow-right.png)
Difference Between Plant Cell and Animal Cell
![arrow-right](/cdn/images/seo-templates/arrow-right.png)