Difference Between Chemical And Physical Change With Examples

What Is Chemical Change?

A chemical change happens when one chemical substance is transformed into one or more different substances such as when ion becomes rust. Chemical changes occur throughout the process of chemical reactions and the resulting substances have different properties because their atoms and molecules are arranged differently.

Chemists categorize chemical changes into three main classes:

  • Inorganic chemical changes. Inorganic chemical changes involve the reaction of elements and compounds that, in general do not involve carbon. The changes typically take place in laboratories or on a larger scale in heavy industries. Typical types of change include neutralization (mixing acids with base, resulting in water and salt), oxidizing including combustion, redox reactions etc.
  • Organic chemical changes.  Organic chemical changes deals with the chemistry of carbon and the elements and compounds with which it reacts. These compounds include mineral oil and all of its products and much of the output of industries manufacturing pharmaceuticals, paints, detergents, cosmetics, fuels etc. other examples of organic chemical changes include cracking heavy hydrocarbon at an oil refinery to create more gasoline from crude oil. Other reactions include methylation, condensation reactions, polymerization, halogenations etc.   
  • Biochemical changes. Biochemical changes deals with the chemistry of the growth and activity of living organisms. It is chemistry where most reactions are controlled by complex proteins referred to as enzymes.

 Examples Of Chemical Changes

  • Burning wood
  • Souring milk
  • Mixing acid and base
  • Digesting food
  • Cooking an egg
  • Heating sugar to form caramel
  • Baking a cake
  • Rusting of iron

What You Need To Know About Chemical Change

  • A chemical change is a change in which the atom configuration of a substance completely changes and a new product/substance is formed.
  • In a chemical change, the mass of a substance does change.
  • Chemical change is an irreversible process in nature. Though some changes are reversible with additional chemical reaction.
  • The process involves change in chemical properties and composition of the substance.  
  • In a chemical change, energy is generated in form of heat, light, sound etc.
  • Chemical change is a permanent change.
  • A chemical change is always accompanied by one or more new substances.
  • In chemical change process, there is absorption and evolution of energy.
  • Chemical changes affect both physical and chemical properties.
  • Original substance cannot be obtained by simple physical methods.

What Is Physical Change?

A physical change is a type of change in which the form of matter is altered but one substance is not transformed into another. Physical changes occur when objects or substances undergo a change that does not change their chemical composition.  Many physical changes also involve the rearrangement of atoms most noticeably in the form of crystals. Physical changes are usually reversible.

A physical change involves a change in physical properties. Examples of physical properties include melting, transition to a gas, change of strength, change of durability, changes to crystal form, textural changes, shape, size, color, volume and density.

Examples Of Physical Changes

  • Crumpling a sheet of aluminum foil
  • Melting an ice cube
  • Casting silver in a mold
  • Breaking a bottle
  • Boiling water
  • Evaporating alcohol
  • Shredding paper
  • Sublimation of dry ice carbon dioxide vapor
  • Mixing red and green marbles
  • Sublimation of dry ice
  • Mixing flour, salt and sugar
  • Mixing water and oil

What You Need To Know About Physical Change

  • A physical change is a change in which the molecules of a substance are re-arranged while their real composition remains unaltered.
  • In a physical change, the mass of a substance does not change.
  • A physical change is a reversible process in nature.
  • It involves change in physical properties of the substance, shape, size color etc.
  • Very little or no energy is generated/given out.
  • Physical change is a temporary (short term) change.
  • In physical change, no new substance is formed.
  • Physical change process involves very little or no absorption of energy.
  • Physical changes only affect physical properties such as shape, color, density, volume, size etc.
  • The original form of substance can be regained by simple physical methods.

Also Read: Difference Between Reversible And Irreversible Process

Difference Between Chemical And Physical Change In Tabular Form

BASIS OF COMPARISON CHEMICAL CHANGE PHYSICAL CHANGE
Description A chemical change is a change in which the atom configuration of a substance completely changes and a new product/substance is formed.   A physical change is a change in which the molecules of a substance are re-arranged while their real composition remains unaltered.  
Mass Of The Substance In a chemical change, the mass of a substance does change.   In a physical change, the mass of a substance does not change.  
Reversibility Chemical change is an irreversible process in nature. A physical change is a reversible process in nature.  
Properties Involve The process involves change in chemical properties and composition of the substance.    It involves change in physical properties of the substance, shape, size color etc.  
Energy Generation In a chemical change, energy is generated in form of heat, light, sound etc.   Very little or no energy is generated/given out.  
Nature of Change Chemical change is a permanent change.   Physical change is a temporary (short term) change.  
Formation Of Substances A chemical change is always accompanied by one or more new substances.   In physical change, no new substance is formed.  
Absorption Of Energy In chemical change process, there is absorption and evolution of energy.   Physical change process involves very little or no absorption of energy.  
Affected Properties Chemical changes affect both physical and chemical properties.   Physical changes only affect physical properties such as shape, color, density, volume, size etc.  
Original Substance Original substance cannot be obtained by simple physical methods.   The original form of substance can be regained by simple physical methods.  

Also Read: Difference Between Biodegradable And Non-Biodegradable Substances

Comments are closed.