Question

Which among the following are physical or chemical changes?

(e) Sublimation of solid ammonium chloride

Answer 1

Physical change

• The changes which can be observed and specified like changes in color, hardness, rigidity, fluidity, density, melting point, boiling point, etc. are the physical changes.

Chemical change

• A chemical change is a change that results in the formation of new chemical substances.
• It involves the making or breaking of bonds between atoms.

Sublimation of solid ammonium chloride

• There is no chemical reaction involved in the sublimation of ammonium chloride$\left({\mathrm{NH}}_4\mathrm{Cl}\right)$.
• It only changes from one physical state that is solid to another physical state that is the gaseous state.
• Hence, it is a physical change.