Question

Corrosion a chemical reaction that involves:
A) The inside of the object changing from an element to a compound
B) The surface of the object changing from an element to a compound
C) Nothing happens
D) The surface of the object changes from one element to the other element

Answer 1

Hint: Corrosion involves chemical change that occurs when the metal is exposed to any other external conditions which affects the surface. The answer to this question lies in this fact.

Complete step by step answer:
In our previous chapters of the chemistry subject we have come across the concept of corrosion mainly relating to rusting of iron.
Let us understand what actually corrosion is and how it happens.
- Firstly, corrosion is the naturally occurring process which involves changes in the physical and chemical properties of the refined metal which converts to a more stable form that is either oxides, sulphides or may be hydroxides.
- Corrosion occurs due to several reasons. The main factor which plays a role is the prolonged exposure to air which consists of a mixture of several gases.
- Rusting of iron is the common example we can see in our daily lives. The metal iron reacts with the oxygen and moisture in air exposure to iron oxide which is a compound and this is reddish brown in colour.
- Apart from common corrosion, even electrochemical corrosion also occurs.
Therefore the iron surface basically undergoes corrosion and thus there is change in element to compound.
So, the correct answer is “Option B”.

Note: The main point to be noted here is that corrosion is a process that occurs due to external factors and thus the inside of the object is not affected but the physical and chemical change occurs on the surface of the metal.