\(n_{NaOH}=\dfrac{8}{40}=0,2(mol)\\ PTHH:NaOH+HCl\to NaCl+H_2O\\ \Rightarrow n_{NaCl}=0,2(mol)\\ \Rightarrow m_{muối}=m_{NaCl}=0,2.58,5=11,7(g)\)
NaOH + HCl ---> NaCl + H2O
nNaOH= \(\dfrac{m}{M}\)= \(\dfrac{8}{40}\)=0,2 (mol)
Theo PTPU ta có: nNaCl=nNaOH=0,2 (mol)
=> mNaCl=n.M=0,2.58,5=11,7(gam)