Given the chemist's observations, we can follow these steps to identify the metal:
1. Determine if the metal melts at [tex]$1000^{\circ} C$[/tex]: The metal does not melt when heated to [tex]$1000^{\circ} C$[/tex]. Therefore, only metals with a melting point above [tex]$1000^{\circ} C$[/tex] can be considered. From the table, these metals are:
- Copper: [tex]$1085^{\circ} C$[/tex]
- Nickel: [tex]$1455^{\circ} C$[/tex]
2. Consider electrical conductivity: Of the metals listed in the table, we need to find the one with the best electrical conductivity ranking among the remaining options. The conductivity rankings for the eligible metals are:
- Copper: 2
- Nickel: 5
3. Select the best conductor: The metal with the lower conductivity ranking number is the better conductor. Thus, comparing the rankings:
- Copper has a ranking of 2, which is better than Nickel's ranking of 5.
Therefore, based on these observations and comparisons, the metal the chemist has is:
B. copper.