a, \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

b, \(n_{Zn}=\dfrac{6,5}{65}=0,1\left(mol\right)\)

\(m_{HCl}=100.14,6\%=14,6\left(g\right)\Rightarrow n_{HCl}=\dfrac{14,6}{36,5}=0,4\left(mol\right)\)

Xét tỉ lệ: \(\dfrac{0,1}{1}< \dfrac{0,4}{2}\), ta được HCl dư.

Theo PT: \(n_{H_2}=n_{Zn}=0,1\left(mol\right)\Rightarrow V_{H_2}=0,1.22,4=2,24\left(l\right)\)

b, Theo PT: \(\left\{{}\begin{matrix}n_{HCl\left(pư\right)}=2n_{Zn}=0,2\left(mol\right)\\n_{ZnCl_2}=n_{Zn}=0,1\left(mol\right)\end{matrix}\right.\)

\(\Rightarrow n_{HCl\left(dư\right)}=0,4-0,2=0,2\left(mol\right)\)

Ta có: m _{dd sau pư} = 6,5 + 100 - 0,1.2 = 106,3 (g)

\(\Rightarrow\left\{{}\begin{matrix}C\%_{ZnCl_2}=\dfrac{0,1.136}{106,3}.100\%\approx12,79\%\\C\%_{HCl\left(dư\right)}=\dfrac{0,2.36,5}{106,3}.100\%\approx6,87\%\end{matrix}\right.\)

a)\(n_{Fe}=\dfrac{14}{56}=0,25\left(mol\right)\)

PTHH: Fe + 2HCl → FeCl₂ + H₂

Mol:    0,25    0,5                    0,25

b) \(C_{M_{ddHCl}}=\dfrac{0,5}{0,5}=1M\)

c) \(V_{H_2}=0,25.22,4=5,6\left(l\right)\)

Ta có: \(n_{Zn}=\dfrac{13}{65}=0,2\left(mol\right)\)

a, PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

_____0,2____0,4_____0,2___0,2 (mol)

b, Ta có: m _{dd sau pư} = m_Zn + m _{dd HCl} - m_H2 = 13 + 100 - 0,2.2 = 112,6 (g)

\(\Rightarrow C\%_{ZnCl_2}=\dfrac{0,2.136}{112,6}.100\%\approx24,16\%\)

c, Ta có: m_HCl = 0,4.36,5 = 14,6 (g)

\(\Rightarrow C\%_{HCl}=\dfrac{14,6}{100}.100\%=14,6\%\)

Bạn tham khảo nhé!

a, PTHH:   Zn  +  2HCl  ➝  ZnCl₂  +  H₂

    (mol)       1           2              1          1

    (mol)      0.2

b, n_Zn=13 :65 =0.2 (mol)

Theo PTHH: n_ZnCl2=(0.2x1):1=0.2(mol)

→m_ZnCl2=0.2x(65+2x35.5)=27.2(g)

⇒C%_ZnCl2=27.2:100x100=27.2(%)

c,Theo PTHH: n_HCl =(0.2 x 2) :1=0.4(mol)

➝m_HCl=0.4x(1+35.5)=14.6(g)

⇒C%_HCl=14.6:100x100%=14.6(%)

a)

$Mg + H_2SO_4 \to MgSO_4 + H-2$

b) $n_{H_2SO_4} = n_{Mg} = \dfrac{4,8}{24} = 0,2(mol)$
$C\%_{H_2SO_4} = \dfrac{0,2.98}{200}.100\% = 9,8\%$

$n_{H_2} = n_{Mg} = 0,2(mol)$

$\Rightarrow m_{dd\ A} = 4,8 + 200 - 0,2.2 = 204,4(gam)$
$C\%_{MgSO_4} = \dfrac{0,2.120}{204,4}.100\% = 11,7\%$

c) $V_{H_2} = 0,2.22,4 = 4,48(lít)$

a, \(Zn+2CH_3COOH\rightarrow\left(CH_3COO\right)_2Zn+H_2\)

Bạn bổ sung thêm số liệu của khí thoát ra nhé.

PTHH: \(2Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\uparrow\)

Ta có: \(\left\{{}\begin{matrix}n_{Al}=\dfrac{3,375}{27}=0,125\left(mol\right)\\n_{H_2SO_4}=\dfrac{300\cdot4,9\%}{98}=0,15\left(mol\right)\end{matrix}\right.\)

Xét tỉ lệ: \(\dfrac{0,125}{2}>\dfrac{0,15}{3}\) \(\Rightarrow\) Al còn dư, H₂SO₄ p/ứ hết

\(\Rightarrow\left\{{}\begin{matrix}n_{H_2}=0,15\left(mol\right)\\n_{Al\left(dư\right)}=0,025\left(mol\right)\\n_{Al_2\left(SO_4\right)_3}=0,05\left(mol\right)\end{matrix}\right.\) \(\Rightarrow\left\{{}\begin{matrix}m_{H_2}=0,15\cdot2=0,3\left(g\right)\\m_{Al\left(dư\right)}=0,025\cdot27=0,672\left(g\right)\\m_{Al_2\left(SO_4\right)_3}=0,05\cdot342=17,1\left(g\right)\end{matrix}\right.\)

Mặt khác: \(m_{dd}=m_{Al}+m_{ddH_2SO_4}-m_{Al\left(dư\right)}-m_{H_2}=302,403\left(g\right)\)

\(\Rightarrow C\%_{Al_2\left(SO_4\right)_3}=\dfrac{17,1}{302,403}\cdot100\%\approx5,65\%\)

\(a)2Al + 6CH_3COOH \to 2(CH_3COO)_3Al + 3H_2\\ b)n_{Al} = \dfrac{2,7}{27} = 0,1(mol) ; n_{CH_3COOH} = \dfrac{200.10\%}{60} = \dfrac{1}{3}(mol)\\ n_{CH_3COOH} = \dfrac{1}{3}> 3n_{Al} = 0,3 \to CH_3COOH\ dư\\ n_{H_2} = \dfrac{3}{2}n_{Al} = 0,15(mol) \Rightarrow V_{H_2} = 0,15.22,4 = 3,36(lít)\\ n_{CH_3COOH\ pư} = 3n_{Al} =0,3(mol) \Rightarrow m_{CH_3COOH\ pư} = 0,3.60 = 18(gam)\\ c) m_{dd} = 2,7 + 200 - 0,15.2 = 202,4(gam)\\ n_{(CH_3COO)_3Al} = n_{Al} = 0,1(mol)\\ m_{CH_3COOH\ dư} = 200.10\% - 18 = 2(gam)\\ C\%_{(CH_3COO)_3Al} = \dfrac{0,1.204}{202,4}.100\% = `10,08\%\\ \)

\(C\%_{CH_3COOH} = \dfrac{2}{202,4}.100\% = 0,988\%\)

\(n_{CaCO_3}=\dfrac{6}{100}=0,06mol\)

\(n_{CH_3COOH}=\dfrac{200}{60}=3,33mol\)

\(2CH_3COOH+CaCO_3\rightarrow\left(CH_3COO\right)_2Ca+CO_2+H_2O\)

       3,33        >     0,06                                                          ( mol )

                              0,06            0,06                     0,06             ( mol )

\(V_{CO_2}=0,06.22,4=1,344l\)

\(m_{\left(CH_3COO\right)_2Ca}=0,06.158=9,48g\)

\(m_{ddspứ}=200+6-0,06.12=205,28g\)

\(C\%_{\left(CH_3COO\right)_2Ca}=\dfrac{9,48}{205,28}.100=4,61\%\)

\(n_{CaCO_3}=\dfrac{6}{100}=0,06\left(mol\right)\\ n_{CH_3C\text{OO}H}=\dfrac{200}{60}=3,3\left(G\right)\\ pthh:CaCO_3+2CH_3C\text{OO}H\rightarrow Ca\left(CH_3C\text{OO}\right)_2+H_2O+CO_2\) 
LTL : \(\dfrac{0,06}{1}< \dfrac{3,3}{2}\) 
=> CaCO3 hết 
theo pthh : \(n_{CO_2}=n_{CaCO_3}=0,06\left(mol\right)\) 
\(\Rightarrow V_{CO_2}=0,06.22,4=1,344\left(l\right)\) 
\(\Rightarrow C\%=\dfrac{6}{200}.100\%=3\%\dfrac{\dfrac{ }{ }C\dfrac{ }{ }\dfrac{ }{ }\dfrac{ }{ }\dfrac{ }{ }}{ }\%\)