\(n_{H_2}=\dfrac{v}{22,4}=\dfrac{8,4}{22,4}=0,375mol\)
\(n_{O_2}=\dfrac{v}{22,4}=\dfrac{2,8}{22,4}=0,125mol\)
2H2+O2\(\overset{t^0}{\rightarrow}2H_2O\)
-Tỉ lệ: \(\dfrac{0,375}{2}=0,1875>\dfrac{0,125}{1}\rightarrow\)O2 hết và H2 dư
\(n_{H_2O}=2n_{O_2}=2.0,125=0,25mol\)
\(m_{H_2O}=0,25.18=4,5gam\)