Молекульная масса
H2SO4,KMRO4,CU(OH)2

Mr (H2SO4) = Mr (H2) + Mr (SO4) = 2 + 98 = 100

Mr (KMnO4) = MrK + Mr (MnO4) = 32 + 118 = 159

Mr (Cu(OH)2) = Mr Cu + 2Mr(OH) = 64 + 34 = 98