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\(n_{H2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\)
a) Pt : \(Zn+2HCl\rightarrow ZnCl_2+H_2|\)
1 2 1 1
0,25 0,5 0,25
b) \(n_{HCl}=\dfrac{0,25.2}{1}=0,5\left(mol\right)\)
500ml = 0,5l
\(C_{M_{ddHCl}}=\dfrac{0,5}{0,5}=1\left(M\right)\)
c) \(n_{Zn}=\dfrac{0,5.1}{2}=0,25\left(mol\right)\)
⇒ \(m_{Zn}=0,25.65=16,25\left(g\right)\)
Chúc bạn học tốt
- Cả 2 chất trong hhA đều tác dụng được với dd HCl dư. Nhưng chỉ có Zn tác dụng với dd HCl dư mới sinh ra khí H2
\(n_{H_2}=\dfrac{4,48}{22,4}=0,2\left(mol\right)\\ PTHH:\left(1\right)Zn+2HCl\rightarrow ZnCl_2+H_2\\ \left(2\right)ZnO+2HCl\rightarrow ZnCl_2+H_2O\\ TheoPTHH\left(1\right):n_{Zn}=n_{ZnCl_2\left(1\right)}=n_{H_2}=0,2\left(mol\right)\\ m_{ZnO}=m_{hhA}-m_{Zn}=21,1-65.0,2=8,1\left(g\right)\\ n_{ZnO}=\dfrac{8,1}{81}=0,1\left(mol\right)\\ n_{ZnCl_2\left(2\right)}=n_{ZnO}=0,1\left(mol\right)\\ n_{ZnCl_2\left(tổng\right)}=0,2+0,1=0,3\left(mol\right)\\ m_{ddB}=m_{hhA}+m_{ddHCl}-m_{H_2}=21,1+200-0,2.2=220,7\left(g\right)\\ C\%_{ddZnCl_2}=\dfrac{136.0,3}{220,7}.100\%\approx18,487\%\)
\(n_{H_2}=\dfrac{4,48}{22,4}=0,2mol\\ Zn+2HCl\rightarrow ZnCl_2+H_2\left(1\right)\\ n_{Zn}=n_{H_2}=n_{ZnCl_2\left(1\right)}=0,2mol\\ n_{ZnO}=\dfrac{21,1-0,2.65}{81}=0,1mol\\ ZnO+2HCl\rightarrow ZnCl_2+H_2O\left(2\right)\\ n_{ZnCl_2\left(2\right)}=n_{ZnO}=0,1mol\\ C_{\%B}=C_{\%ZnCl_2}=\dfrac{\left(0,2+0,1\right).136}{21,1+200-0,2.2}\cdot100\%=18,49\%\)
nH2 = \(\dfrac{4,48}{22,4}\) = 0,2 (mol)
Zn + 2HCl ----> ZnCl2 + H2 (1)
ZnO + 2HCl ----> ZnCl2 + H2O (2)
nZn = nZnCl2 (1) = nH2 = 0,2 (mol)
=> mZn = 0.2 x 65 = 13 (g)
=> mZnO = 21,1 - 13 = 8,1 (g)
=> nZnO = 8,1/81 = 0.1 (mol)
nZnCl2 (2) = nZnO = 0.1 (mol)
C%ZnCl2 = \(\dfrac{152\left(0,2+0,1\right)}{21,1+200}\times100\%=20.62\%\)
\(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\)
\(Mg+2HCl\rightarrow MgCl_2+H_2\)
0,2-->0,4----->0,2------->0,2
a
\(V_{H_2}=0,2.22,4=4,48\left(l\right)\)
b
\(CM_{MgCl_2}=\dfrac{0,2}{0,2}=1M\)
c
\(MgCl_2+2NaOH\rightarrow Mg\left(OH\right)_2+2NaCl\)
0,2------>0,4
\(V_{dd.NaOH}=\dfrac{0,4}{2}=0,2\left(l\right)\)
\(Đặt:n_{Na_2CO_3}=a\left(mol\right);n_{K_2CO_3}=b\left(mol\right)\\ Na_2CO_3+2HCl\rightarrow2NaCl+CO_2+H_2O\\ K_2CO_3+2HCl\rightarrow2KCl+CO_2+H_2O\\ CO_2+Ca\left(OH\right)_2\rightarrow CaCO_3\downarrow+H_2O\\ n_{CaCO_3}=n_{CO_2}=0,3\left(mol\right)\\ \Rightarrow\left\{{}\begin{matrix}106a+138b=38,2\\a+b=0,3\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}a=0,1\\b=0,2\end{matrix}\right.\\ a.C\%_{ddHCl}=\dfrac{0,6.36,5}{200}.100=10,95\%\\ b.m_{ddB}=38,2+200-0,3.44=225\left(g\right)\\ C\%_{ddKCl}=\dfrac{74,5.2.0,2}{225}.100\approx13,244\%\\ C\%_{ddNaCl}=\dfrac{58,5.2.0,1}{225}.100=5,2\%\)
\(n_{Zn}=\frac{m}{M}=\frac{23.5}{65}=0,36mol\)
\(m_{HCl}=\frac{200.7,3}{100}=14,6g\)
\(n_{HCl}=\frac{m}{M}=\frac{14,6}{36,5}0,4mol\)
PTHH:
\(Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)
bd 0,36 0,4 0 0(mol)
pứ 0,2 0,4 0,2 0,2(mol)
spứ 0,16 0 0,2 0,2 (mol)
a)\(V_{H_2}=n.22,4=0,2.22,4=4,48\left(l\right)\)
b)\(m_{ZnCl_2}=n.M=0,2.136=27,2g\)
\(m_A=m_{Znpu}+m_{ddHCl}-m_{H_2}=0,2.65+200-0,2.2=212,6g\)\(C\%_{ZnCl_2}=\frac{27,2}{212,6}.100\%=12,79\%\)
a) Zn +2HCl---->ZnCl2 +H2
n\(_{Zn}=\frac{23,5}{65}=0,36\left(mol\right)\)
n\(_{HCl}=\frac{200.7,3}{100.36,5}=0,4\left(mol\right)\)
=> Zn dư( Do tỉ lệ hệ số cân bằng)
Theo pthh
n\(_{H2}=0,2\Rightarrow m_{H2}=0,4\left(g\right)\)
VH2=0,2.22,4=4,48(l)
b)mdd=200+23,5-0,4=223,1(g)
n\(_{ZnCl2}=\frac{1}{2}n_{HCl}=0,2\left(mol\right)\)
C%ZnCl2=\(\frac{0,2.136}{223,1}.100\%=12,19\%\)