Mr(H2CO3) = 1*2 + 12+16*3 = 62
W(H)=Ar(H)*n / Mr(H2CO3) *100% = 1*2 / 62 *100% = 3%
W(C) = Ar(C) * n/ Mr(H2CO3) *100% = 12*1 / 62 *100% = 19%
W(O) = Ar(O) * n / Mr(H2CO3) *100% = 16 * 3 / 62 *100% = 77%
Mr(H2CO3) = 1*2 + 12+16*3 = 62
W(H)=Ar(H)*n / Mr(H2CO3) *100% = 1*2 / 62 *100% = 3%
W(C) = Ar(C) * n/ Mr(H2CO3) *100% = 12*1 / 62 *100% = 19%
W(O) = Ar(O) * n / Mr(H2CO3) *100% = 16 * 3 / 62 *100% = 77%