Từ hai muối X và Y thực hiện các phản ứng sau:
$\displaystyle \begin{array}{l}{X }\!\!~~~\!\!{ }\,\xrightarrow{{{{t}}^{{o}}}}{ }\!\!~~~\!\!{ }\!\!~~~\!\!{ }{{{X}}_{{1}}}{ }\!\!~~~\!\!{ + C}{{{O}}_{{2 }\!\!~~~\!\!{ }}}\\{{{X}}_{{1 }\!\!~~~\!\!{ }}}{+ }{{{H}}_{{2}}}{O }\!\!~~~\!\!{ }\xrightarrow{{}}{{{X}}_{{2}}}\\{{{X}}_{{2}}}{ }\!\!~~~\!\!{ + Y }\!\!~~~\!\!{ }\!\!~~~\!\!{ }\xrightarrow{{}}{ }\!\!~~~\!\!{ X + }{{{Y}}_{{1 }\!\!~~~\!\!{ }}}{+ }{{{H}}_{{2}}}{O}\\{{{X}}_{{2}}}{ }\!\!~~~\!\!{ + 2Y }\!\!~~~\!\!{ }\!\!~~~\!\!{ }\xrightarrow{{}}{ }\!\!~~~\!\!{ X + }{{{Y}}_{{2}}}{ }\!\!~~~\!\!{ + }{{{H}}_{{2}}}{O}\end{array}$
Hai muối X, Y tương ứng là
A. BaCO3, Na2CO3.
B. CaCO3, NaHCO3.
C. MgCO3, NaHCO3.
D. CaCO3, NaHSO4.