Question

matter has many properties. physical properties do not change the composition or chemical nature of the matter. chemical properties represent an ability or inability to undergo a process that does change the composition or chemical nature of the matter. another way to put this is that chemical properties describe the way a substance may change or react to form other substances. distinguishing these is an important skill. classify these as either a chemical property or physical property. chemical property physical property melting point reactivity hardness color ph density toxicity mass combustibility

Explanation:

Physical properties can be observed or measured without changing the substance's chemical composition. Chemical properties involve a substance's ability to undergo chemical changes. Melting point, hardness, color, density, and mass are physical as they don't change the chemical nature. Reactivity, pH, toxicity, and combustibility are chemical as they describe how a substance reacts or changes chemically.

Answer:

Chemical Property: Reactivity, pH, Toxicity, Combustibility
Physical Property: Melting point, Hardness, Color, Density, Mass