ZnS+2HCl (конц) = ZnCl2+H2S
H2S+2NaOH (конц) = Na2S+2H2O
Na2S+ZnSO4=Na2SO4+ZnS
ZnS+4H2SO4=ZnSO4+4SO2+4H2O
H2SO3
M(H2SO3)=2+16*3+32=82 г/моль
М(S)=32 г/моль
w(S)=32/82*100=39.0%
ответ: г)
1. N2O3 + 2KOH = 2KNO2+H2O
2. KNO2+HCl(разб) = KCl+HNO2
Ответ:
дано
m(ppa CaCL2) = 140 g
W(CaCL2) = 10%
m2(CaCL2) = 10 g
m(H2O) = 25 g
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W2(CaCL2)-?
m(ppa CaCL2) = m(ppa CaCL2) + m2(CaCL2) + m(H2O)
m общая (ppa CaCL2) = 140 + 10+25 = 175 g
m1(CaCL2) = 140 * 10% /100% = 14 g
m общая (CaCL2) = m1(CaCL2) + m2(CaCL2) = 14+10 = 24 g
W2(CaCL2) = m общая (CaCL2) / m общая (ppa CaCL2) *100%
W2(CaCL2) = 24 / 175 * 100% = 13.7%
ответ 13.7%
Объяснение: