1.
CTTQ: Na_x^{I}(CO_3)_y^{II}
Theo QTHT: x.I=y.II->x/y=2/1->x=2;y=1
->Na_2CO_3
CTTQ: Fe_x^{II}Cl_y^{I}
Theo QTHT: x.II=y.I->x/y=1/2->x=1;y=2
->FeCl_2
2.
M_{H_2SO_4}=1.2+32+16.4=98(a m u)
\%m_H={2.1}/{98}.100\%≈2,04\%
\%m_S={32}/{98}.100\%≈32,65\%
\%m_O=100-2,04-32,65=65,31\%
M_{BaCO_3}=137+12+16.3=197(a m u)
\%m_{Ba}={137}/{197}.100\%≈69,54\%
\%m_C={12}/{197}.100\%≈6,09\%
\%m_O=100-6,09-69,54=24,37\%
