3KCIO2 + K2Cr2O7 + 4H2SO4 → 3<span>KCIO3 + Cr2(SO4)3 + K2SO4+4H2O
Cl+3-2e=Cl+5
Cr+6+3e=Cr+3</span>
А.
1) 4Li + O2 = 2Li2O
2) Li2O + H2O = 2LiOH
3) LiOH + HCl = LiCl + H2O
4) 2Li + 2H2O = 2LiOH + H2
5) Li2O + 2HCl = 2LiCl + H2O
Б.
1) 2Na + O2 = Na2O2
2) 2Na2O2 = 2Na2O + O2
3) Na2O + H2O = 2NaOH
4) 2NaOH + H2SO4 = Na2SO4 + 2H2O
5) Na2O + 2HNO3 = NaNO3 + H2O
M(cu2(oh)2co3)= 128+80+2+12=222 г/моль
w(cu)=128/222*100%=58%
w(o)=80/222*100%=36%
w(h)=2/222*100%=1%
w(c)=12/222*100%=5%
удачи