Объяснение:
1. Са(ОН)2
Мr(Са(ОН)2)= 74
w(Ca)=Ar(Ca)×n÷Мr(Са(ОН)2÷100%=40÷74×100%=54%
Аналогічно:
w(О)=32÷74×100%=43%
w(Н)=2÷74×100%=2,7%
2. КМnO4
Mr(KMnO4) = 158
w(K) = Ar(K)×n÷Mr(KMnO4)*100% = 39×1÷158×100% =25%
w(Mn) = Ar(Mn)×n÷Mr(KMnO4)×100% = 55×1÷158×100% =35%
w(O) = Ar(O)×n÷Mr(KMnO4)×100% = 16×4÷158×100% =40%
3. MgBr2
Mr(MgBr2) = 184
w(Mg) = Ar(Mg)×n÷Mr(MgBr2)*100% = 24×1÷184×100% =13%
w(Br) = Ar(Br)×n÷Mr(MgBr2)×100% = 80×2÷184×100% =87%
4. KClO3
Mr(KClO3) = 122,5
w(K) = Ar(K)×n÷Mr(KClO3)*100% = 39×1÷122,5×100% =32%
w(Cl) = Ar(Cl)×n÷Mr(KClO3)×100% = 35,5×1÷122,5×100% =29%
w(O) = Ar(O)×n÷Mr(KClO3)×100% = 16×3÷122,5×100% =39%
