Is a very reactive metal a good reducing agent?
True; reactive metals such as lithium, sodium and magnesium are good reducing agents. To be a good reducing agent, an element needs to be able to lose electrons easily. The tendency to lose electrons depends on how tightly the outermost electrons are coupled to the nucleus of the atom, which itself depends on the nuclear charge of the nucleus, which attracts electrons, and shielding from any lower electron shells, which decreases the effect of the nuclear charge on the outermost shell of electrons.
