Ответ - 3
w = m(KCl)/mраствора = 25г/500г = 0,05(или 5%)
M(Al2O3)=102 g/mol
W(O)=16*3/102*100%=47.06%
M(Fe2O3)=160 g/mol
W(O)=48/160*100%=30%
W(O) в Al2O3>W(O) вFe2O3
<span>P + Br2 + H2O => H3PO4 +
</span> KClO3 + NaBr + H2SO4 => KCl + Br2 + <span>K2SO4 + H2O
</span>Mg + H2SO4(конц) => H2S + <span>Mg SO4 + H2O
</span>Cu + HNO3(РАЗБ) => NO +<span>Cu (NO3)2 + H20
</span>K2Cr2O7 + FeSO4 + H2SO4 => Cr2SO4)3 +<span>Fe2(SO4 )3 + K2SO4 + H2 O
</span>KMnO4 + NaNO2 + H2O => MnO2 +<span>KOH + NaNO3
</span>NaAsO2 + I2 + NaOH => Na3AsO4 +<span>NaI + H2O
</span><span>P + Br2 + H2O => H3PO4 + HBr
</span><span>Mn(OH)2 + Cl2 + KOH => MnO2 +KCl + H2O
</span>NaVO3 + Zn + H2SO4 => VSO4 + ZnSO4 + H2O<span>
S + NaClO + KOH => K2SO4 +</span> H2O<span>+NaCl
</span>K3[Cr(OH)6] + Cl2 + KOH => K2CrO4 + H2O +KCl
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