Ответ:Mr (Ca3(PO4)2) = Ar (Ca) * N (Ca) + Ar (P) * N (P) + Ar (O) * N (O) = 40 * 3 + 31 * 2 + 16 * 4 * 2 = 310.
Объяснение:
4p+5o2=2p2o5 неуверена что правильно))
№1
C2H6->C2H5OH->CH3COH->CH3COOH
C2H6 + Сl2 = C2H5Cl + HCl
C2H5Cl + KOH = C2H5OH + KCl
C2H5OH + CuO = CH3COH + Cu + H2O
CH3COH + Ag2O = CH3COOH +2Ag
№3
C2H4->C2H5Cl->C2H5OH->C2H4
C2H4+HCl=C2H5Cl+HCl
C2H5Cl+NaOH=C2H5OH+NaCl
C2H5OH=C2H4+H2O
№4
CH4->CH2O->CH3OH->CH3COOH->H2CO3
CH4+O2=CH2O+H2O
CH2O+Cu+H2O=CH3OH+CuO
CH3OH+CO=CH3COOH
CH3COOH<span> + NaHCO3 =CH3COONa + H2O + CO2</span>