Дано
m(Ba(NO3)2=4.66 g
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m(Na2SO4)-?
Xg 4.66 g
Na2SO4+Ba(NO3)2-->BaSO4+2NaNO3
142 261
M(Na2SO4)=142 g/mol
M(Ba(NO3)2)=261g/mol
X/142 = 4.66 / 261
X=2.54 g
ответ 2.54 г
2SeCl2 + 3H2O = Se + H2SeO3 + 4HCl:
Se+2 +2e- = Se | 2 | 2 | 1 | - окис-ь
Se+2 -2e- = Se+4 | 2 | | 1 | - восст-ь.
PRIVET, Na2CO3 plus H2SO4 polucaetsya Na2SO4 plus H2O plus CO2 eto molekulyarniy vid . 2Na STEPENYU PLUS plus CO3 STEPENYU 2MINUS plus 2H STEPEN PLUS plus SO4 STEPEN 2MINUS STRELKA 2Na STEPEN PLUS plus SO4 STEPEN 2MINUS plus H2O plus CO2 . ETO POLNOYE IONNOYE URAVNENIYE.
CO3 STEPEN 2MINUS plus 2HSTEPEN PLUS strelka H2O plusCO2 . ETO KRATKOYE IONNOYE URAVNENIYE
Fe+S=FeS+Q
v(Fe)=28/56=0.5 моль
=> Q=48.8*2=97.6
K3PO4+ALCL3=3KCL+ALPO4
3K+PO4+AL+3CL=3K+CL+ALPO4