W(S)=Ar(S)*i : Mr(K2S)=
Mr(K2S)=2*39+32=110 W(S)=32/110=0.2909=29.09%
Mr(K2S) = 39*2 + 32 = 110 W(K) = Ar(K) *n / Mr(K2S) *100% = 39*2 / 110 *100% = 71% W(S) = Ar(S) *n / Mr(K2S) *100% = 32*1 / 110 *100% = 29%