W=m(в-ва)/m(р-ра)×100%
m(H2SO4)=0.25*450=112.5
1)C3H8+CL2--(квант света)-->C3H7CL
2)C3H7CL+KOH(СПИРТ)-->H3C-CH=CH2+KCL+H2O
3)C3H7CL+KOH(ВОДНЫЙ)-->H3C-CH2-CH2-OH+KCL
1)CH3COONa+H2SO4->CH3COOH+Na2SO4
2)CH3COOH+C2H5OH-->CH3C(O)OC2H5
3)CH3C(O)OC2H5+H2O->CH3COONa+C2H5OH
0 +5 +2 -3
4Zn + 10HNO3 = 4Zn(NO3)2 + NH4NO3 + 3H2O
-2e +8e