Which of these is not a physical property of matter? a density b boiling point c malleability d combustibility

Explanation:

Matter has physical and chemical properties.

A physical property can be measured or observed without changing the chemical composition of the matter, this matter will remain being the same matter after observing or measuring its physical properties.

Some examples of physical properties are density, boiling point, malleability, mass, volume, freezing point, ductibility, among many others.

On the other hand, chemical properties are only observed when a chemical change takes place. In this case the matter undergoes a chemical reaction and the original substance becomes one or more different substances.

Combustibility is the property of ungergoing a combustion reaction. The combustion reactions are those in which matter reacts with oxygen releasing energy and light.

Organic matter undergoes combustion producing carbon dioxide and water.

An example of combustion is the burning of methane:

As you see, to observe the combustibility of methane it must undergo a chemical change, so this is a chemical property.