a. \(PTHH:Zn+2HCl--->ZnCl_2+H_2\uparrow\)

b. Áp dụng định luật bảo toàn khối lượng, ta có:

\(m_{Zn}+m_{HCl}=m_{ZnCl_2}+m_{H_2}\)

\(\Leftrightarrow m_{H_2}=m_{Zn}+m_{HCl}-m_{ZnCl_2}=6,5+7,3-13,6=0,2\left(g\right)\)

\(a.Zn+2HCl\rightarrow ZnCl_2+H_2\\ b.m_{ZnCl_2}=13,6\left(g\right)\)

a, \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

b, \(n_{Zn}=\dfrac{39}{65}=0,6\left(mol\right)\)

Theo PT: \(n_{HCl}=2n_{Zn}=1,2\left(mol\right)\Rightarrow m_{HCl}=1,2.36,5=43,8\left(g\right)\)

c, \(n_{H_2}=n_{Zn}=0,6\left(mol\right)\Rightarrow V_{H_2}=0,6.24,79=14,874\left(l\right)\)

d, - Quỳ tím hóa đỏ do HCl dư.

\(n_{HCl}=\dfrac{7,3}{36,5}=0,2\left(mol\right)\)

PTHH: Zn + 2HCl --> ZnCl₂ + H₂

          0,1<---0,2------>0,1--->0,1

=> m_Zn = 0,1.65 = 6,5(g)

=> V_H2 = 0,1.22,4 = 2,24(l)

=> m_ZnCl2 = 0,1.136 = 13,6(g)

\(n_{HCl}=\dfrac{7.3}{36.5}=0.2\left(mol\right)\)

\(Zn+2HCl\rightarrow ZnCl_2+H_2\)

\(0.1........0.2........0.1..........0.1\)

\(m_{Zn}=0.1\cdot65=6.5\left(g\right)\)

\(m_{ZnCl_2}=0.1\cdot136=13.6\left(g\right)\)

\(V_{H_2}=0.1\cdot22.4=2.24\left(l\right)\)

Zn + 2HCl \(\rightarrow\) ZnCl₂ + H₂

\(n_{HCl}=\dfrac{7,3}{36,5}=0,2mol\)

\(\Rightarrow n_{Zn}=\dfrac{0,2}{2}=0,1mol\\ m_{Zn}=0,1.65=6,5g\)

\(\Rightarrow n_{H_2}=\dfrac{0,2}{2}=0,1mol\\ V_{H_2}=0,1.22,4=2,24l\)

\(\Rightarrow n_{ZnCl_2}=\dfrac{0,2}{2}=0,1mol\\ m_{ZnCl_2}=0,1.\left(65+35,5.2\right)=13,6g\)

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

PT: \(Zn+2HCl\rightarrow ZnCl_2+H_2\)

_____0,2____0,4___________0,2 (mol)

\(\Rightarrow m_{HCl}=0,4.36,5=14,6\left(g\right)\)

b, \(V_{H_2}=0,2.24,79=4,958\left(l\right)\)

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

____________0,2__2/15 (mol)

\(\Rightarrow m_{Fe}=\dfrac{2}{15}.56=\dfrac{112}{15}\left(g\right)\)

Số mol của 13 gam Zn:

\(n_{Zn}=\dfrac{m}{M}=\dfrac{13}{65}=0,2\left(mol\right)\)

PTHH: \(Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\)

            1     :   2      :     1      :      1 (g)

          0,2\(\rightarrow\) 0,4       :     0,2  :       0,2  (mol)

a,Khối lượng của 0,4 mol HCl:

\(m_{HCl}=n.M=0,4.36,5=14,6\left(g\right)\)

b, Thể tích khí H2:

\(V_{H_2}=n.24,79=0,2.24,79=4,958\left(l\right)\)

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

Khối lượng của \(\dfrac{2}{15}\) mol Fe:

\(n_{Fe}=\dfrac{m}{M}=\dfrac{2}{\dfrac{15}{56}}\approx7,5\left(g\right)\)

\(a,Zn+H_2SO_4\rightarrow ZnSO_4+H_2\\ b,n_{H_2}=\dfrac{7,437}{24,79}=0,3mol\\ n_{Zn}=n_{H_2SO_4}=n_{ZnSO_4}=n_{H_2}=0,3mol\\ m_{Zn}=0,3.65=19,5g\\ c,C_{M_{H_2SO_4}}=\dfrac{0,3}{0,05}=6M\\ d,m_{ZnCl_2}=0,3.136=40,8g\)

a) Zn + 2HCl --> ZnCl₂ + H₂

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

PTHH:  Zn + 2HCl --> ZnCl₂ + H₂

_____0,2->0,4------->0,2---->0,2

=> m_HCl = 0,4.36,5 = 14,6 (g)

c) _mZnCl2 = 0,2.136 = 27,2 (g)

d) V_H2 = 0,2.24,79 = 4,958(l)

a và b,\(n_{Zn}=\dfrac{13}{65}=0,2mol\)

PTHH: Zn + 2HCl \(\rightarrow\) ZnCl₂ + H₂

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

\(m_{HCl}=0,4.36,5=14,6g\)

c, \(m_{ZnCl_2}=0,2.136=27,2g\)

d, \(V_{H_2}=0,2.22,4=4,48l\)

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

PTHH:

\(Zn+H_2SO_4\rightarrow ZnSO_4+H_2\)

0,1       0,1             0,1        0,1

\(m_{H_2SO_4}=0,1.98=9,8\left(g\right)\)

\(m_{ZnSO_4}=0,1.161=16,1\left(g\right)\)

\(V_{H_2}=0,1.24,79=2,479\left(l\right)\)