Which term is used to refer to an observable trait in the context of physical properties?

• A. Reaction
• B. Characteristic
• C. Element
• D. Molecule

Answer: (B)

Verified step by step guidance

1. In the context of physical properties, an observable trait is referred to as a 'characteristic'.
2. Physical properties are attributes that can be observed or measured without changing the substance's chemical identity.
3. Examples of physical characteristics include color, density, melting point, boiling point, and solubility.
4. The term 'reaction' refers to a process in which substances interact to form new substances, not a physical trait.
5. The terms 'element' and 'molecule' refer to types of substances, not observable traits or characteristics.