The reaction of an alkali metal with liquid water becomes increasingly vigorous from…
CHEMISTRY · Single correct · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
The reaction of an alkali metal with liquid water becomes increasingly vigorous from Li to Cs. Which of the following statements best explains this trend?
(a) Down the group, the electron affinity becomes more negative, making the atoms more eager to gain electrons.
(b) Down the group, increased shielding and a larger atomic radius decrease the ionization energy, so the metal atom loses its valence electron more readily.
(c) Down the group, the ionic radius decreases, so the smaller cation is more strongly hydrated, releasing more energy in the reaction.
(d) Down the group, electronegativity increases, strengthening the metal–oxygen bond that forms during the reaction.