Which of the following is a set fo reducing agents ?

Options

A. ` Cr_2O_7^(2-), CrO_4^(2-), Na`
B. `I^(-) , Na, Fe^(2+)`
C. `F^(-) , Cl^(-) , MnO_4^(-)`
D. `HNO_3, Fe^(2+), F_(2)`

Answer

B

Explanation

A species can act as a reducing agent if the central atom is not present in its highest oxidation state. In option (4), N in `HNO_3` has the highest oxidation state , ` +5` . In option (3), `Mn` in ` MnO_4^(-)` has the highest oxidation state, ` +7`, and in option (4), `Cr` in ` Cr_2O_7^(2-)` has the highest oxidation state, ` +6` Thus, all the species in option (2) will act as reducing agents.