4.1.2 The standard equilibrium constant expression *Equilibria involving gases H2(g)+I2(g)=2HI(g) [p(HI)/p2 K= pe=100kpa [p(H2)/pe]p(I,)/pe] *Equilibria in aqueous solution: Sn2(aq)+2Fe3+(aq)-Sn4+(aq)+2Fe2+(aq) ke_Lc(Sn "c)lle(Fc2)2 [c(Sn 2/ce )l[c(Fe 3*/c)] ce=1 mol.H1