4Na+O2-to>2Na2O
0,1-----0,2 mol
n Na=\(\dfrac{11,5}{23}\)=0,5 mol
n O2=\(\dfrac{3,2}{32}\)=0,1 mol
=>Na dư , dư 0,025 mol
=>m Nadư=0,025.23=0,575 g
=> m sản phẩm = 0,2.62=12,4g
a.
\(n_{Na}=\dfrac{11,5}{23}=0,5\left(mol\right)\)
\(n_{O_2}=\dfrac{3,2}{32}=0,1\left(mol\right)\)
PTHH : 4Na + O2 -> 2Na2O
0,4 0,1 0,2 ( mol )
Xét tỉ lệ : \(\dfrac{0,5}{4}>\dfrac{0,1}{1}\)=> Na dư , O2 đủ
\(m_{Na\left(dư\right)}=\left(0,5-0,4\right).23=2,3\left(g\right)\)
b) \(m_{Na_2O}=0,2.62=12,4\left(g\right)\)