n_h2=\(\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

a) 3Mg + 2H₃PO_{4 ---->} Mg₃(PO₄)₂ +3H₂

0,3.......0,2............................0,1 0,3

_b) m_Mg3(PO4)2=n_mg3(po4)2.m_mg3(po4)2=0,1.262=26,2 g

c) m_h3po4=n_h3po4.m_{h3p04=0,2.98=19,6 g}

\(n_{Fe}=\dfrac{22,4}{56}=0,4\) (mol) (1)

Phương trình hóa học : 

Fe + 2HCl ---> FeCl₂ + H₂ (2) 

Từ (1) và (2) ta có \(n_{FeCl_2}=n_{H_2}=0,4\) (mol) ; \(n_{HCl}=0,8\left(mol\right)\)

b) => \(m_{\text{muối}}=0,4.\left(56+35,5.2\right)=50.8\left(g\right)\)

c) \(V_{\text{khí}}=0,4.22,4=8,96\left(l\right)\)

d) \(m_{HCl}=0,8.36.5=29,2\left(g\right)\)

\(\Rightarrow C\%=\dfrac{29,2}{200}.100\%=14,6\%\)

a, \(2Al+6HCl\rightarrow2AlCl_3+3H_2\)

b, \(n_{Al}=\dfrac{8,1}{27}=0,3\left(mol\right)\)

\(n_{H_2}=\dfrac{3}{2}n_{Al}=0,45\left(mol\right)\Rightarrow V_{H_2}=0,45.22,4=10,08\left(l\right)\)

c, \(n_{AlCl_3}=n_{Al}=0,3\left(mol\right)\Rightarrow m_{AlCl_3}=0,3.133,5=40,05\left(g\right)\)

d, \(n_{Fe_2O_3}=\dfrac{32}{160}=0,2\left(mol\right)\)

PT: \(Fe_2O_3+3H_2\underrightarrow{t^o}2Fe+3H_2O\)

Có: \(\dfrac{0,2}{1}>\dfrac{0,45}{3}\) → Fe₂O₃ dư.

\(n_{Fe}=\dfrac{2}{3}n_{H_2}=0,3\left(mol\right)\Rightarrow m_{Fe}=0,3.56=16,8\left(g\right)\)

a) Zn + 2HCl --> ZnCl₂ + H₂

b) \(n_{H_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

PTHH: Zn + 2HCl --> ZnCl₂ + H₂

_____0,3<---0,6<----------------0,3

=> m_Zn = 65.0,3 = 19,5(g)

c) m_HCl = 0,6.36,5 = 21,9(g)

a)\(PTHH:Mg+2HCl\xrightarrow[]{}MgCl_2+H_2\)

b) Số mol của magie là:

\(n_{Mg}=\dfrac{m_{Mg}}{M_{Mg}}=\dfrac{3,6}{24}=0,15mol\)

\(PTHH:Mg+2HCl\xrightarrow[]{}MgCl_2+H_2\)

tỉ lệ       :1          2           1               1      mol

số mol  :0,15     0,3        0,15          0,15 mol

Thể tích khí hiđro là:

\(V_{H_2}=n_{H_2}.22,4=0,15.22,4=3,36\left(l\right)\)

c) Khối lượng muối tạo thành là:

\(m_{MgCl_2}=n_{MgCl_2}.M_{MgCl_2}=0,15.95=14,25\left(g\right)\)

d) Khối lượng axit đã dùng là:

\(m_{HCl}=n_{HCl}.M_{HCl}=0,3.36,5=10,95\left(g\right)\)

a) PTHH: Fe + H₂SO₄ ===> FeSO₄ + H₂

b) Ta có: n_Fe = $\frac{14}{56}=0,25\left(mol\right)$

Theo PTHH, n_H2SO4 = n_Fe = 0,25 (mol)

=> m_H2SO4 = 0,25 x 98 = 24,5 (gam)

c) Theo PTHH, n_H2 = n_Fe = 0,25 (mol)

=> V_H2(đktc) = 0,25 x 22,4 = 5,6 (l)

d) Theo PTHH, n_FeSO4 = n_Fe = 0,25 (mol)

=> m_FeSO4(tạo thành) = 0,25 x 152 = 38 (gam)

PTHH: \(Fe+H_2SO_4\rightarrow FeSO_4+H_2\uparrow\)

Ta có: \(n_{Fe}=\dfrac{28}{56}=0,5\left(mol\right)=n_{H_2}=n_{FeSO_4}\)

\(\Rightarrow\left\{{}\begin{matrix}V_{H_2}=0,5\cdot22,4=11,2\left(l\right)\\m_{FeSO_4}=0,5\cdot152=76\left(g\right)\end{matrix}\right.\)

a) \(PTHH:2Al+6HCl\xrightarrow[]{}2AlCl_3+3H_2\)

b) \(n_{H_2}=\dfrac{3,36}{22,4}=0,15\left(mol\right)\)

\(n_{Al}=\dfrac{0,15.2}{3}=0,1\left(mol\right)\)

\(m_{Al}=0,1.27=2,7\left(g\right)\)

c)\(n_{AlCl_3}=\dfrac{0,15.2}{3}=0,1\left(mol\right)\)

\(m_{AlCl_3}=0,1.133,5=13,35\left(g\right)\)

pls help me mng ơi!Tuần sau mnh thi mất r!T_T

a, 2Al + 6HCl -> 2AlCl₃ + 3H₂  (1)

b, n_H2=\(\dfrac{V}{22.4}\)=\(\dfrac{3,36}{22,4}\)=0,15 (mol)

Từ pt (1)

-> n_Al=\(\dfrac{2}{3}\).n_H2 = \(\dfrac{2}{3}\).0,15 = 0,1 (mol)

-> m_Al = n.M = 0,1 . 27 = 2,7 (g)

c, Từ pt (1)

-> n_AlCl3= \(\dfrac{2}{3}\).n_H2 = \(\dfrac{2}{3}\). 0,15 = 0,1 (mol)

-> m_AlCl3= n.M = 0,1 .133.5 = 13,35 (g)

\(a)n_{H_2}=\dfrac{14,874}{24,79}=0,6mol\\2 Al+3H_2SO_4\rightarrow Al_2\left(SO_4\right)_3+3H_2\)

0,4mol     0,6mol          0,2mol           0,6mol

\(m_{Al}=0,4.27=10,8g\\ b)m_{Al_2\left(SO_4\right)_3}=0,2.342=68,4g\\ c)m_{H_2SO_4}=0,6.98=58,8g\)