Which among the following are physical or chemical changes?
Sublimation of solid ammonium chloride.
Which among the following are physical or chemical changes?
Sublimation of solid ammonium chloride.
Physical change: a temporary change, in which no new substance is formed and the chemical composition of the original substance remains the same, even though some of its physical properties like color, state, shape, size, etc. may change.
Characteristics of physical change:
- Identity of substance is maintained.
- The change is temporary
- There is a change in the physical state of the substance but chemical properties remain the same.
Chemical change: A permanent change in which new substances are formed whose chemical and physical properties are completely different from that those of the original substance.
Characteristics of chemical change:
- change is permanent and cannot be reversed.
- one or more new substance is formed.
- composition of the original substance does not remain the same.
- the heat or light may be produced or consumed during the reaction.
- exchange of energy takes place during the reaction.
Sublimation: It is a process of changing of solid state directly to the gaseous state without going through the liquid phase.
Sublimation of solid ammonium chloride () is a physical change because during the sublimation the solid ammonium chloride directly changes to a vapor state without converting into liquid on heating if the heating effect is removed after some time the vapors of ammonium chloride condense back to give solid ammonium chloride. Thus in this whole process, only the state of the substance changes the chemical properties remain the same.
Physical change: a temporary change, in which no new substance is formed and the chemical composition of the original substance remains the same, even though some of its physical properties like color, state, shape, size, etc. may change.
Characteristics of physical change:
- Identity of substance is maintained.
- The change is temporary
- There is a change in the physical state of the substance but chemical properties remain the same.
Chemical change: A permanent change in which new substances are formed whose chemical and physical properties are completely different from that those of the original substance.
Characteristics of chemical change:
- change is permanent and cannot be reversed.
- one or more new substance is formed.
- composition of the original substance does not remain the same.
- the heat or light may be produced or consumed during the reaction.
- exchange of energy takes place during the reaction.
Sublimation: It is a process of changing of solid state directly to the gaseous state without going through the liquid phase.
Sublimation of solid ammonium chloride () is a physical change because during the sublimation the solid ammonium chloride directly changes to a vapor state without converting into liquid on heating if the heating effect is removed after some time the vapors of ammonium chloride condense back to give solid ammonium chloride. Thus in this whole process, only the state of the substance changes the chemical properties remain the same.
