\(m_{Ba\left(OH\right)_2}=\dfrac{342\cdot20\%}{100\%}=68,4\left(g\right)\\ n_{Ba\left(OH\right)_2}=\dfrac{68,4}{137+17\cdot2}=0,4\left(mol\right)\\ PTHH:Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O\)
Theo đề: \(n_{HCl}=2n_{Ba\left(OH\right)_2}=0,8\left(mol\right)\)
\(\Rightarrow m_{HCl}=0,8\cdot36,5=29,2\left(g\right)\\ \Rightarrow C\%_{HCl}=\dfrac{29,2}{100}\cdot100\%=29,2\%\)
\(m_{ct}=\dfrac{20.342}{100}=68,4\left(g\right)\)
\(n_{Ba\left(OH\right)2}=\dfrac{68,4}{171}=0,4\left(mol\right)\)
Pt : \(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O|\)
1 2 1 2
0,4 0,8
\(n_{HCl}=\dfrac{0,4.2}{1}=0,8\left(mol\right)\)
⇒ \(m_{HCl}=0,8.36,5=29,2\left(g\right)\)
\(C_{ddHCl}=\dfrac{29,2.100}{100}=29,2\)0/0
Chúc bạn học tốt
\(Ba\left(OH\right)_2+2HCl\rightarrow BaCl_2+2H_2O\)
\(n_{Ba\left(OH\right)_2}=\dfrac{342.20\%}{171}=0,4\left(mol\right)\\ n_{HCl}=2n_{Ba\left(OH\right)_2}=0,8\left(mol\right)\\ C\%_{HCl}=\dfrac{0,8.36,5}{100}.100=29,2\%\)