1. Mr(H3PO4) = 1*3+31+16*4 = 98 Mr(C12H22O11) = 12*12+22+16*11 = 342 Mr(Ca3(PO4)2) = 40*3+31*2+16*8 = 310 2. HCl, Ar(H):Ar(Cl) = 1:35.5 NaHCO3, Ar(Na):Ar(H):Ar(C):3Ar(O) = 23:1:12:48 3. Mr(H2CO3) = 62 w(O) = 48/62 = 0.774 або 77.4%