Answer
Four valance electrons; Lose electrons.
Work Step by Step
Tin is a main group element. Therefore, its valance electrons are those in the outermost energy principal level. The noble gas configuration for Tin is $[Kr]5s^{2}4d^{10}5p^{2}$. Therefore, Tin has four valance electrons. Since, Tin is a metal, it is expected to lose electrons in chemical reactions.