a) \(\left\{{}\begin{matrix}n_{MgO}=\dfrac{8}{40}=0,2\left(mol\right)\\n_{H_2SO_4}=\dfrac{294.10\%}{98}=0,3\left(mol\right)\end{matrix}\right.\)
PTHH: MgO + H2SO4 ---> MgSO4 + H2O
bđ 0,2 0,3
pư 0,2------>0,2
sau pư 0 0,1 0,2
b) \(m_{ddupư}=8+294=302\left(g\right)\)
c) \(\left\{{}\begin{matrix}C\%_{MgSO_4}=\dfrac{0,2.120}{302}.100\%=7,95\%\\C\%_{H_2SO_4\left(dư\right)}=\dfrac{0,1.98}{302}.100\%=3,25\%\end{matrix}\right.\)