Classify each property as physical or chemical. a. the boiling point of ethyl alcohol b. the temperature at which dry ice evaporates c. the tendency of iron to rust d. the color of gold

Verified step by step guidance

1. Identify the definition of a physical property: a characteristic that can be observed or measured without changing the substance's chemical identity.
2. Identify the definition of a chemical property: a characteristic that describes a substance's ability to undergo a specific chemical change.
3. For part (a), consider whether the boiling point of ethyl alcohol involves a change in chemical identity or just a change in state.
4. For part (b), consider whether the temperature at which dry ice (solid CO2) evaporates involves a change in chemical identity or just a change in state.
5. For part (c), consider whether the tendency of iron to rust involves a change in chemical identity, such as forming a new substance.
6. For part (d), consider whether the color of gold involves a change in chemical identity or is simply an observable characteristic.

Key Concepts

Physical Properties

Physical properties are characteristics of a substance that can be observed or measured without changing its chemical identity. Examples include boiling point, melting point, color, and density. These properties can often be determined through physical changes, such as phase transitions, without altering the substance's chemical structure.

Chemical Properties

Chemical properties describe a substance's ability to undergo chemical changes and transform into different substances. These properties are observed during chemical reactions and include reactivity with other chemicals, flammability, and the tendency to rust. For instance, the tendency of iron to rust is a chemical property because it involves a reaction with oxygen and moisture.

Classification of Properties

Classifying properties as either physical or chemical is essential for understanding how substances behave under various conditions. This classification helps predict how substances will react in different scenarios. For example, knowing that boiling point is a physical property allows us to understand that it can be measured without changing the substance, while recognizing rusting as a chemical property indicates a change in the substance's identity.