Metals ：練習問題

Most metals are found in the Earth's crust as compounds mixed with other substances rather than as pure elements. What does this suggest about the nature of these metals?

Copper was used by humans to make tools and weapons thousands of years before iron. Which statement provides the best scientific explanation for this historical timeline?

Humanity transitioned from the 'Bronze Age' (copper/tin) to the 'Iron Age' primarily because of a technological hurdle in metal extraction. Which statement best explains this delay based on chemical properties?

A student is testing a solid element. He finds that the element has a shiny appearance and conducts electricity well. Which group of elements does this unknown substance most likely belong to?

Which of the following best describes why stainless steel is often used for making kitchen cutlery instead of pure iron, even though iron is the primary component?

While most metals must be extracted from compounds in rocks, some metals can be found in their pure, elemental form in Nature. Name one example of such a metal.

While both iron and copper can be extracted from their respective oxides by heating them with carbon, iron requires a significantly higher temperature for the reaction to occur. Explain this difference by referencing the chemical reactivity of the two metals.

Based on the reactivity series, predict which metal was likely discovered and used by humans earlier: lead (extracted by heating its oxide with carbon) or magnesium (extracted by electrolysis). Explain your reasoning.

Metals are important materials with various applications in our daily lives. Answer the following questions regarding their properties and extraction.

a) Iron (\(Fe\)) is more abundant in the Earth's crust than copper (\(Cu\)), yet copper was discovered and used by humans much earlier. Suggest a reason for this based on the ease of extraction of these metals.

b) Metals are used to build bridges and the frames of large buildings because they can support heavy loads without breaking. State the physical property of metals that makes them suitable for this purpose.

c) Silver (\(Ag\)) is an even better conductor of electricity than copper (\(Cu\)), but copper is used for household electrical wiring instead. Suggest one reason why copper is used instead of silver.

d) The disposal of metal products like aluminium (\(Al\)) cans can cause environmental problems. State one way to help solve the problem of metal waste in our society.

Metals are essential materials in our daily lives, and their applications are determined by their specific physical and chemical properties.

a) Many high-quality cooking pans are designed with a copper base. State the specific physical property of copper that is being utilized for this purpose. (1 point)
b) Metals can be drawn into thin wires. Name this property and describe how it differs from malleability. (2 points)
c) Aluminum is often used for the bodies of aircraft. State two properties of aluminum that make it more suitable for this application than iron. (2 points)