X, Y & Z are three metallic atoms in successive order belonging to the same group such that atomic radii of ‘X’ is the smallest. Which of the three atoms is the best reducing agent?
(a) X
(b) Y
(c) Z
(d) All three have the same reducing power
(c) Z
Explanation:
The greater the tendency to lose electrons, the greater the metallic character and the stronger the reducing power of a metal. As we move down a group, atomic size increases and ionisation energy decreases, so the tendency to lose electrons and thus the reducing power also increases. Therefore, of the three atoms, Z (the lowest member of the group) is the best reducing agent.
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