a) \(m_{HCl}=\frac{200.7,3}{36,5}=14,6\left(g\right)\)
\(n_{HCl}=\frac{14,6}{36,5}=0,4\left(mol\right)\)
\(MxOy+2yHCl-->xMCl_{2y/x}+yH2O\)
\(n_{MxOy}=\frac{1}{2y}n_{HCl}=\frac{0,2}{y}\left(mol\right)\)
\(M_{MxOy}=16,2:\frac{0,2}{y}=81x\)
\(x=1\Rightarrow M_{MxOy}=81\)
\(\Rightarrow x=1\Rightarrow M+16=81\)
\(\Rightarrow M=65\left(Zn\right)\)
CTPT:ZnO
b)\(n_{ZnCl2}=\frac{1}{2}n_{HC_{ }l}=0,2\left(mol\right)\)
\(ZnCl2+2KOH-->Zn\left(OH\right)2+2KCl\)
\(n_{KCl}=2n_{ZnCl2}=0,2\left(mol\right)\)
\(m_{KCl}=0,2.74,5=14,9\left(g\right)\)
a, \(M_xO_y+2yHCl\rightarrow xMCl_{\frac{2y}{x}}+yH_2O\)
Ta có :
\(n_{HCl}=\frac{200.7,3\%}{36,5}=0,4\left(mol\right)\)
\(\Rightarrow n_{MxOy}=\frac{0,2}{y}\left(mol\right)\)
\(M=\frac{16,2}{\frac{0,2}{y}}=81y\)
\(\Rightarrow M_x+16y=81y\Rightarrow M=32,5.\frac{2y}{x}\)
\(\frac{2y}{x}=2\Rightarrow M_X=65\left(\frac{g}{mol}\right)\Rightarrow X:Zn\)
\(\frac{2y}{x}=2\Rightarrow x=y\Rightarrow ZnO\)
b,
\(ZnCl_2+2KOH\rightarrow Zn\left(OH\right)_2+2KCl\)
\(Zn\left(OH\right)_2+2KOH\rightarrow K_2ZnO_2+2H_2O\)
\(n_{K2ZnO2}=n_{ZnCl2}=0,2\left(mol\right)\)
\(\Rightarrow m_{K2ZnO2}=0,2.175=35\left(g\right)\)
