19.座標值為何? (A)190tf(B)180tf(C)170tf(D)160tf

3. Based on the solubility rules, which of the following will occur if solutions of CuSO4(aq) and BaCl2(aq) are mixed? (A) CuCl2 will precipitate; Ba2+ and SO42 – are spectator ions. (B) CuSO4 will precipitate; Ba2+ and Cl – are spectator ions. (C) BaSO4 will precipitate; Cu2+ and Cl– are spectator ions. (D) BaCl2 will precipitate; Cu2+ and SO42 – are spectator ions. (E) No precipitate will form.