Among lead, iron, chromium and copper, which is the least easily oxidized metal
Copper is the least easily oxidized metal among lead, iron, chromium, and copper. Copper has a low reactivity which means it is less likely to lose electrons, making it difficult to oxidize. Lead, iron, and chromium all have a higher reactivity and are more easily oxidized compared to copper.
To determine which metal is the least easily oxidized among lead, iron, chromium, and copper, we can refer to their positions in the electrochemical series or activity series. The electrochemical series is a list of metals arranged in order of their tendency to lose electrons and be oxidized. In general, the higher a metal is in the series, the more easily it oxidizes.
According to the electrochemical series, the order from least to most easily oxidized among the four metals you mentioned is as follows:
1. Copper (Cu)
2. Iron (Fe)
3. Chromium (Cr)
4. Lead (Pb)
Therefore, lead (Pb) is the least easily oxidized metal among the options given.