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Physical properties are characteristics of matter that can be observed or measured without changing the material's chemical composition. They include attributes like color, density, melting point, boiling point, and magnetic properties. For example, the attraction of an iron nail to a magnet is a result of its ferromagnetic nature and is considered a physical property. You can measure or observe these properties without altering the identity of the substance. Iron retains its composition while displaying magnetic attraction, making it a purely physical property. Similarly, wood floating on water is due to its density being less than that of the water. This floating capability also falls under the category of physical properties because it doesn't change the wood's composition.

Chemical properties describe a substance's ability to undergo changes that transform it into different substances. These include flammability, reactivity, and oxidation states. A classic example of a chemical property is the spontaneous ignition of paper at a temperature of 451°F. This type of ignition involves a combustion reaction, transforming the paper into ash and gaseous by-products, distinctly altering its chemical makeup.
The formation of a patina on a bronze statue is another example. This process is a result of oxidation, a chemical reaction between bronze and oxygen in the air, forming a new substance—the patina. Both examples demonstrate how chemical properties involve substantive changes that convert the original material into distinct compounds.

Ferromagnetism is a specific kind of magnetic property found in certain materials such as iron, cobalt, nickel, and their alloys. It is a physical property characterized by the ability of a material to become magnetically aligned with an external magnetic field and retain this alignment even after the external field is removed.
In the case of the iron nail, ferromagnetism explains why it is attracted to a magnet without any alteration to its chemical makeup. The alignment of tiny magnetic domains within the material facilitates this strong attraction. Ferromagnetism is solely a physical property because it relates to the structure and behavior of materials under magnetic influence without a chemical reaction occurring.

A combustion reaction is a specific type of chemical reaction where a substance combines with oxygen to produce heat and light. This exothermic process often results in the formation of different new substances. When paper ignites at 451°F, it undergoes combustion—a classic chemical reaction. During this process, the cellulose in paper reacts with atmospheric oxygen, releasing energy in the form of heat and forming new substances like carbon dioxide, water vapor, and ash.
Combustion reactions are vital for various applications, including energy generation and propulsion. They are a clear demonstration of a chemical property, as they reorder the molecular structure of the involved molecules, leading to entirely new products.