A chemist is trying to identify a sample of metal that is listed in this table. She passes an electrical current through the metals listed in the table; it's one of the best conductors. Then she heats the metal to [tex]$1000^{\circ} C$[/tex]. The metal doesn't melt. Which type of metal does the chemist have?
| Material | Melting Point ([tex]${}^{\circ} C$[/tex]) | Electrical Conductivity Ranking |
| :------- | :----------------------------- | :----------------------------- |
| aluminum | 660 | 3 |
| copper | 1085 | 2 |
| zinc | 420 | 4 |
| silver | 962 | 1 |
| nickel | 1455 | 5 |
A. aluminum
B. copper
C. Zinc
D. silver
E. nickel
Answer (1)
Identify the best electrical conductor from the table.
Check if the metal melts at 100 0 ∘ C .
If the metal doesn't melt, it's the correct answer.
Copper is the correct answer because it has good electrical conductivity and a melting point above 100 0 ∘ C .
B
Explanation
Problem Analysis We are given a table of metals with their melting points and electrical conductivity rankings. The chemist has a metal that is one of the best conductors and does not melt at 100 0 ∘ C . We need to identify the metal from the table.
Identify Best Conductors First, let's identify the metals with the best electrical conductivity. According to the table, silver has the best electrical conductivity ranking (1).
Check Melting Point of Silver Next, we need to check if silver melts at 100 0 ∘ C . The melting point of silver is 96 2 ∘ C . Since the metal does not melt at 100 0 ∘ C , silver is not the correct answer.
Check Melting Point of Copper Let's consider the next best conductor. Copper has an electrical conductivity ranking of 2. The melting point of copper is 108 5 ∘ C . Since 1000^{\circ} C"> 108 5 ∘ C > 100 0 ∘ C , copper does not melt at 100 0 ∘ C . Therefore, copper is the correct answer.
Final Answer The metal the chemist has is copper.
Examples
Understanding the properties of different metals, like their melting points and electrical conductivity, is crucial in many real-world applications. For example, when designing electrical circuits, engineers need to choose metals that are good conductors of electricity and can withstand the operating temperatures without melting. Copper is often used in wiring because of its high conductivity and relatively high melting point. Similarly, in high-temperature applications like furnaces, metals with very high melting points, such as nickel, are used to prevent structural failure.
