Using 1.0x 10^-6 M as the criterion for quantitative removal, determine whether it is feasible to use
(a) SO₄ ^2- to separate Ba²⁺ and Sr²⁺ in a solution that is initially 0.030 M in Sr²⁺ and 0.15 M in Ba²⁺.
(b) SO₄ ^2- to separate Ba²⁺ and Ag⁺ in a solution that is initially 0.040 M in each cation. For Ag₂SO₄, K_sp = 1.6 x 10^-5.
(c) OH^- to separate Be²⁺ and Hf⁴⁺ in a solution that is initially 0.030 M in Be²⁺ and 0.020 M in Hf⁴⁺. For Be(OH)₂, K_sp = 7.0 x 10^-22, and for Hf(OH)₄, K_sp = 4.0 x 10^-26.
(d) IO₃^- to separate In³⁺ and Tl⁺ in a solution that is initially 0.20 M in In³⁺ and 0.07 M in Tl⁺. For In(IO₃)₃, K_sp = 3.3 x 10^-11, and for TlIO₃, K_sp = 3.1 x 10^-6.