Phy change no new substance is formed it is reversible chem change is oop to that

Difference between a physical and chemical change

Physical and chemical changes are two types of transformations that matter can undergo. Although both types of changes involve a modification in the composition of substances, they differ in various aspects. Let's delve into the details of each type of change and explore their dissimilarities.

Physical Change:

A physical change is a transformation in which the substance's appearance or state is altered, but its chemical composition remains unchanged. The atoms and molecules involved in the substance do not rearrange during a physical change. Some key characteristics of physical changes include:

Change in appearance: Physical changes primarily involve modifications in the substance's appearance, such as size, shape, or texture. For example, crushing a can, boiling water, or dissolving sugar in water are all physical changes.

No new substances formed: In a physical change, the original substance does not convert into a different substance with different properties. The particles in the substance retain their original identity. For instance, when water freezes into ice, the chemical properties of water remain the same.

Reversible: Physical changes are often reversible, meaning that the original substance can be recovered. For example, melting ice can be reversed by freezing it again.

Chemical Change:

A chemical change, also known as a chemical reaction, occurs when substances react with one another, resulting in the formation of new substances with different chemical properties. During a chemical change, the atoms and molecules rearrange, breaking and forming new chemical bonds. Key characteristics of chemical changes include:

Formation of new substances: In a chemical change, the reactants undergo a transformation, resulting in the formation of new substances. For example, when iron rusts, it reacts with oxygen in the air to form iron oxide.

Change in energy: Chemical changes often involve the release or absorption of energy in the form of heat, light, or sound. This change in energy can be observed, such as in the combustion of wood, which releases heat and light.

Irreversible: Unlike physical changes, chemical changes are typically irreversible. Once the reaction occurs and new substances are formed, it is challenging to revert them back to the original substances.

Conclusion:

In summary, physical changes involve modifications in the appearance or state of a substance without altering its chemical composition, while chemical changes result in the formation of new substances with different properties. Physical changes are usually reversible and do not involve the formation of new substances, while chemical changes are often irreversible and involve the rearrangement of atoms and molecules to create new substances. Understanding the distinction between these two types of changes is crucial in various scientific fields, such as chemistry and physics.