Question

Cr2O2=>K2CrO4=>K2Cr2=>Cr2(SO4)3=>K3{Cr(OH)6}

Answer 1

2 Cr2O3 + 4 K2CO3 + 3 O2 = 4 K2CrO4 + 4 CO2 2 K2CrO4 + H2SO4 = K2Cr2O7 + K2SO4 + H2O K2Cr2O7 + 3 Na2SO3 + 4 H2SO4 = Cr2(SO4)3 + K2SO4 + 3 Na2SO4 + 4 H2O Cr2(SO4)3 + 12 KOH(изб) = 2 K3[Cr(OH)6] + 3 K2SO4