Which term describes a characteristic that can only be observed by changing the identity of the substance?

• A. Physical Property
• B. Chemical Property
• C. Physical Change
• D. Ionic Compound

Answer: (B)

A chemical property is a characteristic that can only be observed when the substance undergoes a chemical change, which transforms its identity into new substances. This is different from physical properties, which you can observe without changing what the substance is (like color, melting point, or density). Observing a chemical property typically involves a reaction that alters the substance, such as flammability or reactivity with another reagent, where new substances are formed. The other options don’t fit because a physical property is seen without changing identity, a physical change changes form or state but not the substance’s identity, and an ionic compound is a type of substance, not a property.