a, \(Na_2O+H_2SO_4\rightarrow Na_2SO_4+H_2O\)

b, Số mol \(H_2SO_4\) là: \(n_1=V.C_M=0,5.0,5=0,25\) (mol)

Số mol \(Na_2SO_4\) là \(n_2=\dfrac{28,4}{142}=0,2\) (mol)

Do \(n_2< n_1\) nên \(H_2SO_4\) còn dư

Suy ra số mol \(Na_2O\) tham gia phản ứng là: \(n=n_2=0,2\) (mol)

Khối lượng là: \(m_{Na_2O}=0,2.62=12,4g\)

nZn=0,4mol

nH2SO4=0,5mol

PTHH: Zn+H2SO4=>ZnSO4+H2

            0,4:0,5=> nH2SO4 dư theo nZn

p/ư:      0,4->0,4----->0m4---->0,4

=> VH2=0,4.22,4=8,96ml

b) mZnSO4 tạo thành : m=0,4.161=64,4g

c) ta có mđ H2SO4=1,12.500=560g

mddZnSO4=26+560-0,4.2=585,2g

=> C%(ZnSO4)=64,4:585,2.100=11%

\(a,PTHH:Na_2O+H_2O\rightarrow2NaOH\\ \Rightarrow n_{NaOH}=2n_{Na_2O}=2\cdot\dfrac{37,2}{62}=0,6\cdot2=1,2\left(mol\right)\\ \Rightarrow C_{M_{NaOH}}=\dfrac{1,2}{0,5}=2,4M\\ b,PTHH:2NaOH+H_2SO_4\rightarrow Na_2SO_4+H_2O\\ \Rightarrow n_{H_2SO_4}=\dfrac{1}{2}n_{NaOH}=0,6\left(mol\right)\\ \Rightarrow m_{H_2SO_4}=0,6\cdot98=58,8\left(g\right)\\ \Rightarrow m_{dd_{H_2SO_4}}=\dfrac{58,8\cdot100\%}{20\%}=294\left(g\right)\\ \Rightarrow V_{dd}=\dfrac{294}{1,14}\approx257,9\left(ml\right)\)

Lần sau bạn đăng tách từng bài ra nhé.

Câu 1:

a, \(Na_2O+H_2O\rightarrow2NaOH\)

\(n_{Na_2O}=\dfrac{15,5}{62}=0,25\left(mol\right)\)

Theo PT: \(n_{NaOH}=2n_{Na_2O}=0,5\left(mol\right)\Rightarrow C_{M_{NaOH}}=\dfrac{0,5}{0,5}=1\left(M\right)\)

b, \(2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O\)

Theo PT: \(n_{H_2SO_4}=\dfrac{1}{2}n_{NaOH}=0,25\left(mol\right)\)

\(\Rightarrow m_{H_2SO_4}=0,25.98=24,5\left(g\right)\)

\(\Rightarrow m_{ddH_2SO_4}=\dfrac{24,5}{20\%}=122,5\left(g\right)\)

\(\Rightarrow V_{ddH_2SO_4}=\dfrac{122,5}{1,14}\approx107,46\left(ml\right)\)

Câu 3: \(n_{CO_2}=\dfrac{8,96}{22,4}=0,4\left(mol\right)\)

PT: \(CO_2+Ca\left(OH\right)_2\rightarrow CaCO_{3\downarrow}+H_2O\)

\(n_{CaCO_3}=n_{CO_2}=0,4\left(mol\right)\Rightarrow m_{CaCO_3}=0,4.100=40\left(g\right)\)

Câu 4: \(n_{CuSO_4}=\dfrac{32}{160}=0,2\left(mol\right)\)

\(n_{BaCl_2}=\dfrac{20,8}{208}=0,1\left(mol\right)\)

PT: \(CuSO_4+BaCl_2\rightarrow BaSO_{4\downarrow}+CuCl_2\)

Xét tỉ lệ: \(\dfrac{0,2}{1}>\dfrac{0,1}{1}\), ta được CuSO₄ dư.

Theo PT: \(n_{BaSO_4}=n_{BaCl_2}=0,1\left(mol\right)\Rightarrow m_{BaSO_4}=0,1.233=23,3\left(g\right)\)

Câu 2:

\(n_{HCl}=0,3.0,2=0,06\left(mol\right)\)

PT: \(HCl+NaOH\rightarrow NaCl+H_2O\)

Theo PT: \(n_{NaOH}=n_{NaCl}=n_{HCl}=0,06\left(mol\right)\)

\(\Rightarrow V_{NaOH}=\dfrac{0,06}{1,5}=0,04\left(l\right)\)

\(\Rightarrow C_{M_{NaCl}}=\dfrac{0,06}{0,3+0,04}=\dfrac{3}{17}\left(M\right)\)

a, \(n_{Na_2O}=\dfrac{7,75}{62}=0,125\left(mol\right)\)

PTHH: Na₂O + H₂O → 2NaOH

Mol:     0,125                    0,25

b, \(C_{M_{ddNaOH}}=\dfrac{0,25}{0,25}=1M\)

c, 

PTHH: 2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O

Mol:        0,25       0,125

\(m_{ddH_2SO_4}=\dfrac{0,125.98.100}{20}=61,25\left(g\right)\)

\(\Rightarrow V_{ddH_2SO_4}=\dfrac{61,25}{1,14}=53,728\left(ml\right)\)

n_Fe = 11.2/56 = 0.2 (mol) 

Fe + H2SO4 => FeSO4 + H2 

0.2____0.2_______0.2___0.2 

mH2SO4 = 0.2*98 = 19.6 (g) 

mdd H2SO4 = 19.6*100/10 = 196 (g) 

m dd sau phản ứng = 11.2 + 196 - 0.4 = 206.8 (g) 

mFeSO4 = 0.2*152 = 30.4 (g) 

C% FeSO4 = 30.4/206.8 * 100% = 14.7% 

Vdd H2SO4 = mdd H2SO4 / D = 196 / 1.14 = 171.9 (ml) 

CM FeSO4 = 0.2 / 0.1719 = 1.16 M 

n_Fe = 11.2/56 = 0.2 (mol) 

Fe + H2SO4 => FeSO4 + H2 

0.2____0.2_______0.2___0.2 

mH2SO4 = 0.2*98 = 19.6 (g) 

mdd H2SO4 = 19.6*100/10 = 196 (g) 

m dd sau phản ứng = 11.2 + 196 - 0.4 = 206.8 (g) 

mFeSO4 = 0.2*152 = 30.4 (g) 

C% FeSO4 = 30.4/206.8 * 100% = 14.7% 

Vdd H2SO4 = mdd H2SO4 / D = 196 / 1.14 = 171.9 (ml) 

CM FeSO4 = 0.2 / 0.1719 = 1.16 M 

a) PTHH: \(KOH+HCl\rightarrow KCl+H_2O\)

b) Ta có: \(n_{KCl}=0,15\cdot0,5=0,075\left(mol\right)=n_{KOH}\) \(\Rightarrow m_{KOH}=0,075\cdot56=4,2\left(g\right)\)

c) PTHH: \(KCl+AgNO_3\rightarrow KNO_3+AgCl\downarrow\)

Theo PTHH: \(n_{KCl}=0,075\left(mol\right)=n_{AgNO_3\left(p.ứ\right)}=n_{KNO_3}=n_{AgCl}\)

\(\Rightarrow n_{AgNO_3\left(dư\right)}=0,075\cdot120\%-0,075=0,015\left(mol\right)\)

\(\Rightarrow\left\{{}\begin{matrix}m_{AgCl}=0,075\cdot143,5=10,7625\left(g\right)\\C_{M_{KNO_3}}=\dfrac{0,075}{0,5+2}=0,03\left(M\right)\\C_{M_{AgNO_3\left(dư\right)}}=\dfrac{0,015}{2,5}=0,006\left(M\right)\end{matrix}\right.\)

d) Coi như khi cô cạn không bị hao hụt muối

Ta có: \(m_{muối.khan}=m_{KNO_3}+m_{AgNO_3\left(dư\right)}=0,075\cdot101+0,015\cdot170=10,125\left(g\right)\)