Ar(Fe) = 56
Mr(O₂) = 16·2=32
Mr(NO) = 14 + 16 = 30
Mr(Fe₂O₃) = 56·2 + 16·3 = 160
Mr(Na₂SO₄) = 23·2+32+16<span>·4 = 142</span>
<span>2Ca + O2 → 2CaO
</span><span>ZnCO3 → ZnO + CO2
</span><span>2K + 2HCl → 2KCl + H2
</span>Na + 3P → Na3P
<span>2Fe + 3Cl2 → 2FeCl3
</span><span>C + 2FeO → 2Fe + CO2
</span><span>2P + 3S → P2S3
</span><span>N2 + 3H2 → 2NH3
</span><span>3K2O + P2O5 → 2K3PO4
</span><span>2LiOH + H2S → Li2S + 2H2O</span>
1) Cu(OH)2 + 2HCl = CuCl2 + 2H2O
Ответ: (б)
2) (а)
3) (а) NaOH + HNO3 = NaNO3 + H2O
P2O5+3H2O=2H3PO4
1 кмоль 2 кмоль
n(P2O5)=28.4/142=0.2 кмоль
n(H3PO4)=2*0.2=0.4 кмоль
m(H3PO4)=98*0.4=39.2 кг
w(H3PO4)=36/39.2*100%=91.84%