Answer:
The correct answer is :a metal railing rusting in damp weather is an example of a chemical change.
Explanation:
Physical property is defined as the property of a substance which becomes evident during physical changes. Example: Melting point
A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions.
Example: Melting of ice
Chemical property is defined as the property of a substance which becomes evident during chemical changes. Example: Reactivity with other substances
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions.
Example: Corrosion of iron called as rusting.
Rust is ferric oxide [tex]Fe_2O_3[/tex].
[tex]4Fe+3O_2\righatarrow 2Fe_2O_3[/tex]
A metal railing rusting in damp weather is an example of chemical change because composition of an iron rail is changing.
[tex]4Fe+3O_2\rightarrow 2Fe_2O_3[/tex]
Where as other examples given are the examples of physical change.
