设28克铁完全反应克制的m克氢气;用20g氢气填充气球需n克铁
Fe+H2SO4→FeSO4+H2↑
56`````````````````2
28`````````````````m
n``````````````````20
列式56/28=2/m
56/n=2/20
m=1,n=560
所以28克铁完全反应可制得1克氢气;用20g氢气填充气球需要560克铁
设28克铁完全反应克制的m克氢气;用20g氢气填充气球需n克铁
Fe+H2SO4→FeSO4+H2↑
56`````````````````2
28`````````````````m
n``````````````````20
列式56/28=2/m
56/n=2/20
m=1,n=560
所以28克铁完全反应可制得1克氢气;用20g氢气填充气球需要560克铁