Massaverhoudingen bepalen

In deze video leer je over het zelf bepalen van massaverhoudingen uit een kloppende reactievergelijking. Ook leer je over de Wet van behoud van massa oftwel de Wet van Lavoisier. Uitwerkingen zelf oefenen: 2 P2O5 (s) -- 4 P (s) + 5 O2 (g) Molecuulmassa P2O5 = 2 x 31,0 u + 5 x 16,0 u = 142,0 u 2 moleculen P2O5 dus 2 x 142,0 u = 284,0 u Atoommassa P = 31,0 u 4 atomen dus 4 x 31,0 u = 124,0 u Molecuulmassa O2 = 32,0 u 5 moleculen dus 5 x 32,0 = 160,0 u Massaverhouding: 2 P2O5 (s) -- 4 P (s) + 5 O2 (g) 284,0 : 124,0 : 160,0 C3H8O (l) + 3 O2 (g) -- 3 CO (g) + 4 H2O (l) Molecuulmassa C3H8O = 3 x 12,0 u + 8 x 1,0 u + 1 x 16,0 u = 60,0 u 1 molecuul C3H8O dus 1 x 60,0 u = 60,0 u Molecuulmassa O2 = 2 x 16,0 u = 32,0 u 3 moleculen O2 dus 3 x 32,0 u = 96,0 u Molecuulmassa CO = 1 x 12,0 u + 1 x 16,0 u= 28,0 u 3 moleculen CO dus 3 x 28,0 u = 84,0 u Molecuulmassa H2O = 2 x 1,0 u + 1 x 16,0 = 18,0 u 4 moleculen H2O dus 4 x 18,0 u = 72,0 u Massaverhouding: C3H8O (l) + 3 O2 (g) -- 3 CO (g) + 4 H2O (l) 60,0 : 96,0 : 84,0 : 72,0 2 C12H22O11 (s) -- 24 C(s) + 22 H2 (g) + 11 O2 (g) Molecuulmassa C12H22O11 = 12 x 12,0 u + 22 x 1,0 u + 11 x 16,0 u = 342,0 u 2 moleculen C12H22O11 dus 2 x 342,0 u + = 684,0 u Atoommassa C = 12,0 u 24 atomen C dus 24 x 12,0 u = 288,0 u Molecuulmassa H2 = 1 x 1,0 u = 2,0 u 22 moleculen H2 dus 22 x 2,0 u = 44,0 u Molecuulmassa O2 = 2 x 16,0 = 32,0 u 11 moleculen O2 dus 11 x 32,0 u = 352,0 u Massaverhouding: 2 C12H22O11 (s) -- 24 C(s) + 22 H2 (g) + 11 O2 (g) 684,0 : 288,0 : 44,0 : 352,0