question_answer

Which of the following pairs of ions would be expected to form precipitate when their dilute solution are mixed [CPMT 1976]

A)                                                                                             \[N{{a}^{+}},\,SO_{3}^{2-}\]                

B)                                                                                           \[NH_{4}^{+},\,CO_{3}^{2-}\]  

C)                                                                                               \[N{{a}^{+}},\,{{S}^{-2}}\]                

D)                                                                            \[F{{e}^{+3}},\,PO_{4}^{-3}\]