Question

1.Cate grame de hidrogen se vor degaja inurma reactiei dintre zinc si acid sulfuric,daca se consuma 10 g solutie de acid sulfuric cu c=20%?
2.Apa contine:
a)11,11% H si 88,89% O
b)11,11% O si 88,89% H
c)30% H SI 60% O

Answer 1

1. C=md/ms*100 => md=C*ms/100=20*10/100 = 2g H2SO4

Zn + H2SO4 -> ZnSO4 + H2

98g H2SO4.......................2g H2
2g H2SO4.........................xg H2

x=2*2/98 = Calculeaza !!

2. MH2O = 2AH+AO = 2*1+16=18g/mol

%H=mH/MH2O*100 = 2/18*100 = Calculeaza !!

%O = 16/18*100 = Calculeaza !!