Rusting of an article made up of iron is called (a) corrosion, and it is a physical as well as chemical change (b) dissolution, and it is a physical change (c) corrosion, and it is a chemical change d) dissolution, and it is a chemical change
The answer is c) corrosion, and it is a chemical change.
Explanation :
Rusting of iron is corrosion, and it’s a chemical change because rust is a chemical compound called hydrated iron oxide
Fe2O3. nH2O, iron(III), which is different from elemental iron.
Physical changes are those changes in which substance identity is not changed, and it can get back to its original form. For example, water freezing to ice can be melted back to waste, whereas chemical changes are those in which the original substance identity is changed, and they cannot be restored to their original form.
On adding solid solutes to the solvent, some solute dissolves, and their concentration increases in the solution. This process is known as dissolution.
Crystallisation is a process in which solute particles in a solution collide with the solid solute particles to get separated out of the solution.
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