1. дано
m(Ca)= 60 g
--------------------------
n(O2)-?
60 X
2Ca+O2-->2CaO M(Ca)= 40 g/mol M(O2) = 32 g/mol
2*40 32
X = 60*32 / 80
X = 24 g
n(O2)= m/M = 24/32 = 0.75 mol
ответ 0.75 моль
2. дано
V(H2)= 560 L
------------------
m(H2O)-?
560 L X
2H2+O2-->2H2O Vm = 22.4 L/mol M(H2O)= 18 g/mol
2*22.4 2*18
X = 560*36 / 44.8 = 450 g
ответ 450 г