Which is an example of a chemical change

Answer : The correct option is, (C) metal corroding in salt water.

Explanation :

Chemical change : It is a change where changes occurs in the chemical composition and thus resulting in the formation of new compound or substance. It is an irreversible reaction.

The indication of chemical changes are :

Formation of gas bubbles.

Formation of precipitate.

Change in color.

Change in temperature.

Change in volume.

Change in smell or taste.

Evolution of heat, light and sound.

Physical change : It is a change in which shape and size of a substance changes. In this there is no change in the chemical composition of the substance and no new substance is forming. It is a reversible reaction.

The indication of chemical changes are :

Change in shape.

Change in form.

Change in size.

Change in phase.

(A) Mixing of poster colors : It is a physical change because only changes takes place in the phase from liquid phase to vapor phase.

(B) Formation of clouds : It is a physical change because only changes takes place in the phase from vapor phase to liquid phase.

(C) Metal corroding in salt water : It is a chemical change because the chemical composition of substance changes.

(D) Sugar dissolving in water : It is a physical change because only changes takes place in the phase from solid phase to liquid phase.

(E) Separating salt from seawater : It is a physical change because only changes takes place in the phase from liquid phase to solid phase.

Hence, the correct option is, (C) metal corroding in salt water.