Ta có:
\(V_{Dd_{NaOH}}=\frac{200}{1000}=0,2\left(l\right)\)
\(V_{dd_{HCl}}=\frac{300}{1000}=0,3\left(l\right)\)
\(V_{dd_{Ba\left(OH\right)2}}=\frac{25}{1000}=0,025\left(l\right)\)
\(n_{NaOH}=0,2.1=0,2\left(mol\right)\)
\(n_{Ba\left(OH\right)2}=0,025.0,5=0,0125\left(mol\right)\)
\(n_{HCl}=0,3.1=0,3\left(mol\right)\)
\(NaOH+HCl\rightarrow NaCl+H_2O\)
\(n_{HCl_{pư}}=0,2\left(mol\right)\)
Vì n NaOH < n HCl
\(\Rightarrow n_{HCl_{dư}}=n_{HCl_{bđ}}-n_{HCl_{pư}}=0,3-0,2=0,1\left(mol\right)\)
\(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O\)