M(H3PO4)р-ра=200*1,25=250гm(H3PO4)в р-ре=250*0,4=100г
P2O5 + 3H2O -> 2H3PO4 1 2n(P2O5)=14,2/142=0,1моль; n(H3PO4)=0,1*2=0,2моль; m(H3PO4)=0,2*98=19,6г;m(H3PO4)общ.=100+19,6=119,6г; w(H3PO4)=119,6/(250+14,2)=0,4527(45,27%
2KBr+Cl2=2KCl+Br2
2KCl+ZnO=ZnCl2+K2O
ZnCl2+2NaOH=Zn(OH)2+2NaCl
4 НCl + O2 → 2 H2O + 2 Cl2 ↑
K2O + Cl2 → KClO + KCl
AgNO3 + KCl → AgCl ↓ + KNO3