Question

3 which of the following statements is true about the physical properties of objects? a they can be observed without changing the substance chemically b they cannot be observed without changing the substance chemically c they include examples such as acidity and flammability d they can be changed by burning, magnetizing, or cutting

Explanation:

Physical properties are characteristics of a substance that can be observed or measured without changing the substance's chemical composition. For example, color, density, and melting point are physical properties. Option A is correct as it aligns with the definition of physical properties. Option B is incorrect because physical properties do not require a chemical change to be observed. Option C is wrong as acidity and flammability are chemical properties (they involve chemical changes). Option D is incorrect because burning is a chemical change (it alters the substance chemically), while magnetizing and cutting are physical changes but the statement's overall context is off - physical properties themselves are not "changed" by burning (a chemical process).

Answer:

A. They can be observed without changing the substance chemically.