Metals are extracted from their ores by either displacement with carbon or by electrolysis.
Explain
why copper can be extracted using displacement with carbon by comparing the reactivities of the two elements.
Copper can be extracted using displacement with carbon because carbon is more reactive than copper. In the reactivity series, carbon is found above copper. This means that carbon has a higher tendency to form compounds compared to copper.
During the extraction process, carbon (usually in the form of coke) is heated with the copper ore known as copper(II) oxide (CuO). The carbon reacts with oxygen in the copper oxide, forming carbon dioxide (CO2) and leaving behind pure copper. This is essentially a redox reaction, where carbon acts as the reducing agent and copper oxide is reduced to copper.
The reactivity of an element determines its ability to displace another element from its compound. In this case, carbon is able to displace copper from its oxide because carbon is higher in the reactivity series. If copper were more reactive than carbon, the displacement reaction would not occur, and an alternative method, such as electrolysis, would be needed for copper extraction.
On the other hand, electrolysis is used to extract metals that are more reactive than carbon, such as aluminum. In electrolysis, a direct electric current is passed through a molten metal compound, causing the metal ions to be reduced at the cathode (negative electrode) and deposited as pure metal. The metal compound is typically an ionic compound, and the metal ions move towards the cathode due to their positive charges and are reduced.
In summary, copper can be extracted by displacement with carbon because carbon is more reactive than copper and can displace copper from its oxide. This method is used due to the position of copper in the reactivity series.