Cho sơ đồ sau:  X + Y → CaCO₃ + BaCO₃ + H₂O

X,Y có thể là

H₂SO₄, Na₂CO₃, BaCl₂, Na₂SO₄

H₂SO₄, HCl, NaCl, NaNO₃

Ba(OH)₂, NaNO₃, Na₂CO₃, BaCl₂

NaOH, NaNO₃, Na₂CO₃, HCl

$NH_4^ + ,\,N{a^ + },\,C{l^ - },\,SO_4^{2 - }$

$NH_4^ + ,\,N{a^ + },\,C{l^ - },\,O{H^ - }$

$NO_3^ - ,\,F{e^{2 + }},\,C{l^ - },\,{H^ + }$

$B{a^{2 + }},\,N{a^ + },\,C{l^ - },\,SO_4^{2 - }$

$N{a^ + },\,\,M{g^{2 + }},\,\,NO_3^ - ,\,\,SO_4^{2 - }$

$N{a^ + },\,\,{K^ + },\,\,HSO_4^ - ,\,\,O{H^ - }$

$B{a^{2 + }},\,\,A{l^{3 + }},\,\,NO_3^ - ,\,\,C{l^ - }$

$F{e^{3 + }},\,\,C{u^{2 + }},\,\,SO_4^{2 - },\,\,C{l^ - }$

(1), (2), (3), (6).

(1), (3), (5), (6).  

(2), (3), (4), (6).

(3), (4), (5), (6).

0,1

0,2

0,3

0,4

0,01 và 0,03.

0,01 và 0,01.

0,03 và 0,02.  

0,02 và 0,01.

dung dịch chứa ${\text{N}}{{\text{a}}^ + }\,0,1M;\,\,B{a^{2 + }}\,0,1M;\,\,{K^ + }\,0,15M;\,\,C{l^ - }\,0,25M;\,\,NO_3^ - \,0,1M$

dung dịch chứa  ${\text{C}}{{\text{a}}^{{\text{2}} + }}\,0,2M;\,\,{{\text{K}}^ + }\,0,25M;\,\,C{l^ - }\,0,25M;\,\,NO_3^ - \,0,4M$

dung dịch chứa ${{\text{K}}^ + }\,0,1M;\,\,N{a^ + }\,0,2M;\,\,NO_3^ - \,0,05M;\,\,C{H_3}CO{O^ - }\,0,05M;\,\,C{l^ - }\,0,2M$

dung dịch chứa  ${\text{M}}{{\text{g}}^{2 + }}\,0,2M;\,\,{K^ + }\,0,1M;\,\,NH_4^ + \,0,1M;\,\,SO_4^{2 - }\,0,25M;\,\,C{l^ - }\,0,05M;\,\,NO_3^ - \,0,05M$