Answer: a. Zreduces varphi^(2+) to varphi{:[z+varphi^(2+)longrightarrowz^(2+)+varphi],[x" reduces "z^(2+)t_(0)z],[x+z^(2+)longrightarrowx^(2+)+z]:}So onden of reactivity isx > z > 9xx can reduce both z^(2+)&varphi^(2+) 15S. The reactions given ane -{:[A+Q^(2+)longrightarrowA^(2+)+Q],[z+A^(2+)longrightarrowZ^(2+)+A]:}i. Since A can reduce Q^(2+) and also Q^(2+) is reduced ley the other metals, hence A is a stronger reducing agent than S.i2. From the above reactions it is concheded that the neducing ability of the metals ane in the following orden -x > z > A > Qx can reduce z^(2+),A^(2+),varphi^(2+)Z can reduce A^(2+),varphi^(2+)A can reduce only rho^(2+)iii. The specisn given ane -A,A^(2+),z,z^(2+),varphi,varphi^(2+),x,x^(2+).The stnongest oxidizing agent is that species which is neduced most easily. It means the species that can easily accept electrons to get reduced. So this oxidizing ag ... See the full answer