Final answer:
Flammability is a chemical property, while melting point, boiling point, and density are physical properties.
Step-by-step explanation:
Flammability is a chemical property. It refers to the ability of a substance to catch fire or burn when exposed to flames or heat. Chemical properties are characteristics of a substance that describe how it interacts with other substances or changes in composition.
On the other hand, melting point, boiling point, and density are all physical properties of a substance. The melting point is the temperature at which a solid substance changes to a liquid state, the boiling point is the temperature at which a liquid substance changes to a gaseous state, and density is the mass of a substance per unit volume.