Which one of the following pairs of substances could be used to construct a single redox electrode (i.e., they have an element in common, but in different oxidation states)?

Question

Quizplus · Accepted Answer

MnO and Mn can be used to construct a single redox electrode because they have the same element, manganese, but in different oxidation states (+2 for Mn and +4 for MnO). This allows for a redox reaction to occur between the two species, making them suitable for use in a redox electrode. The other pairs of substances do not have an element in common in different oxidation states, so they cannot be used to construct a single redox electrode.

Which One of the Following Pairs of Substances Could Be