Question

State whether each of the following is a physical or a chemical property of copper: (a) shiny metallic luster (b) high melting point (c) conducts heat (d) reacts with oxygen

Short answer

Shiny, melting point, and conductivity are physical properties; reacts with oxygen is a chemical property.

Step-by-step solution

Introduction to Concepts

To solve this exercise, we need to distinguish between physical and chemical properties. A physical property can be observed or measured without changing the substance's identity. Examples include color, melting point, and conductivity. A chemical property describes a substance's potential to undergo chemical changes, such as reactivity with other chemicals.

Analyze Shiny Metallic Luster

Copper's shiny metallic luster is a physical property. It is an observable trait that does not involve changing copper's chemical composition.

Evaluate High Melting Point

The high melting point of copper is a physical property. It is a measure of temperature at which copper changes from solid to liquid while its chemical composition remains unchanged.

Assess Conductivity of Heat

Copper's ability to conduct heat is a physical property. This property can be observed by measuring copper's efficiency in transferring thermal energy, without altering its chemical structure.

Examine Reaction with Oxygen

Copper's tendency to react with oxygen is a chemical property. This property involves a chemical change where copper interacts with oxygen to form a new substance (copper oxide), altering its chemical identity.

Key concepts

Chemical Properties

When we talk about chemical properties, we're diving into the fascinating world of how substances behave when they undergo chemical changes. These properties reveal how a substance interacts with other substances. It's like peeking into a substance's potential for transformation. Chemical properties are not immediately visible but rather come to light during chemical reactions. So, for instance, they might tell us whether copper tarnishes when exposed to the air or how it reacts when combined with other elements or compounds.

• **Reactivity with Oxygen**: This is a prime example of a chemical property. Copper reacts with oxygen, especially when exposed to moist air, to form copper oxide. This reaction changes copper's chemical makeup.
• **Tendency to Corrode**: Over time, copper can also corrode, forming patina, which acts as a protective layer. Such reactivity showcases a chemical transformation.

Understanding these properties is crucial for applications in chemistry and materials science, where predicting chemical changes can affect everything from product longevity to safety.

Physical Properties

Physical properties are like a substance's surface level details. They are the traits you can notice or measure without changing what the substance is at a chemical level. Think of physical properties as the descriptive aspects you can observe with your senses or measure.

• **Color and Appearance**: Copper's shiny metallic luster falls into this category. It is a trait you notice right away and doesn't involve altering its chemical structure.
• **Melting Point**: The high melting point is another physical property. It refers to the temperature where copper transitions from solid to liquid, while still remaining chemically the same.
• **Conductivity**: Copper is also well known for its high thermal and electrical conductivity. This means it effectively transfers heat and electricity without changing its chemical identity.

Physical properties are crucial in practical applications, including construction, electronics, and plumbing, since they impact a material's usability and effectiveness.

Copper Reactivity

Copper's behavior when it interacts with other substances is a fascinating area of study. Understanding copper's reactivity helps us in both protecting it from unwanted reactions and utilizing its potential in various chemical processes.

• **Reaction with Air**: Copper reacts slowly with oxygen, leading to a gradual transformation into copper oxide. This is evident when copper surfaces develop a greenish layer, commonly seen on old statues and rooftops.
• **Acid Reactions**: While copper is generally resistant to corrosion, it reacts with some acids, like nitric acid, forming different copper compounds. This reactivity is significant in chemical engineering and material sciences.

Studying the reactivity of copper aids in its various industrial applications. By understanding how copper reacts, we can better harness its properties for manufacturing, construction, and even art.