a) \(n_{CO_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

PTHH: CaCO₃ + 2HCl ---> CaCl₂ + CO₂ + H₂O

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

=> m = 0,3.100 = 30 (g)

b) \(C\%_{HCl}=\dfrac{0,6.36,5}{150}.100\%=14,6\%\)

Câu 1:

a. PTHH: MgCl₂ + HCl ---x--->

CaCO₃ + 2HCl ---> CO₂↑ + H₂O + CaCl₂ (1)

b. Ta có: \(n_{CO_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

Theo PT₍₁₎: \(n_{HCl}=2.n_{CO_2}=2.0,3=0,6\left(mol\right)\)

Đổi 400ml = 0,4 lít

=> \(C_{M_{HCl}}=\dfrac{0,6}{0,4}=1,5M\)

c. PTHH: HCl + NaOH ---> NaCl + H₂O (2)

Vậy chất tác dụng với nước bắp cải tím là NaCl (muối ăn.)

Vậy dung dịch sau phản ứng làm nước bắp cải tím thành màu xam lam đậm.

Câu 2:

a. PTHH: CuO + H₂SO₄ ---> CuSO₄ + H₂O

b. Ta có: \(n_{CuO}=\dfrac{8}{80}=0,1\left(mol\right)\)

Ta lại có: \(C_{\%_{H_2SO_4}}=\dfrac{m_{H_2SO_4}}{100}.100\%=19,6\%\)

=> \(m_{H_2SO_4}=19,6\left(g\right)\)

=> \(n_{H_2SO_4}=\dfrac{19,6}{98}=0,2\left(mol\right)\)

Ta thấy: \(\dfrac{0,1}{1}< \dfrac{0,2}{1}\)

Vậy H₂SO₄ dư.

Theo PT: \(n_{CuSO_4}=n_{CuO}=0,1\left(mol\right)\)

=> \(m_{CuSO_4}=0,1.160=16\left(g\right)\)

Ta có: \(m_{dd_{CuSO_4}}=8+100=108\left(g\right)\)

=> \(C_{\%_{CuSO_4}}=\dfrac{16}{108}.100\%=14,81\%\)

nCO2=0,2mol

PTHH: 2HCl+CaCO3=>CaCl2+CO2+H2O

        0,4mol<-0,2mol<-0,2mol<-0,2mol->0,2mol

=> mHCl tham gia : 0,4.36,5=14,6g

=> C%HCl=14,6:100.100=14,6%

b)mCaCO3 tham gia : 0,2.100=20g

c) m muối thu được :0,2.111=22,2g

theo định luật btoan khối lượng ta có : m(CaCl2)=mHCl+mCaCO3-mCO2-mH2o

=100+20-0,2.44-0,1.18=109,4

=> C% muối: 22,2/109,4.100=20,29%

a,\(n_{CO_2}=\dfrac{2,24}{22,4}=0,1\left(mol\right)\)

PTHH: CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O

Mol:      0,1            0,2                          0,1

\(m_{CaCO_3}=0,1.100=10\left(g\right)\)

b,\(C\%_{ddHCl}=\dfrac{0,2.36,5.100\%}{150}=4,87\%\)

c,m_{dd sau pứ}= 10+150-0,1.44 = 151,2 (g)

\(C\%_{ddCaCl_2}=\dfrac{0,1.111.100\%}{151,2}=7,34\%\)

\(n_{Zn}=\dfrac{26}{65}=0,4\left(mol\right)\\ pthh:Zn+2HCl\rightarrow ZnCl_2+H_2\uparrow\) 
           0,4       0,8        0,4           0,4
\(a,V_{H_2}=0,4.22,4=8,96\left(l\right)\\ b,C\%_{HCl}=\dfrac{0,8.36,5}{150}.100\%=19,5\%\\ c,m_{\text{dd}}=26+150-\left(0,4.2\right)=175,2\left(g\right)\\ C\%_{ZnCl_2}=\dfrac{0,4.136}{175,2}.100\%=31\%\)

\(n_{Fe}=\dfrac{5,6}{56}=0,1\left(mol\right)\)

Pt : \(Fe+2HCl\rightarrow FeCl_2+H_2|\)

        1         2              1          1

       0,1     0,2            0,1       0,1

a) \(n_{H2}=\dfrac{0,1.1}{1}=0,1\left(mol\right)\)

\(V_{H2\left(dktc\right)}=0,1.22,4=2,24\left(l\right)\)

b) \(n_{HCl}=\dfrac{0,1.2}{1}=0,2\left(mol\right)\)

100ml = 0,1l

\(C_{M_{ddHCl}}=\dfrac{0,2}{0,1}=2\left(M\right)\)

c) \(n_{FeCl2}=\dfrac{0,1.1}{1}=0,1\left(mol\right)\)

\(C_{M_{FeCl2}}=\dfrac{0,1}{2}=0,05\left(M\right)\)

 Chúc bạn học tốt

\(n_{Mg}=\dfrac{4,8}{24}=0,2\left(mol\right)\\ a.Mg+2HCl\rightarrow MgCl_2+H_2\\ n_{H_2}=n_{MgCl_2}=n_{Mg}=0,2\left(mol\right)\\ V_{H_2\left(đktc\right)}=0,2.22,4=4,48\left(l\right)\\ b.n_{HCl}=0,2.2=0,4\left(mol\right)\\ m_{ddHCl}=\dfrac{0,4.36,5.100}{7,3}=200\left(g\right)\\ c.m_{ddsau}=4,8+200-0,2.2=204,4\left(g\right)\\ C\%_{ddMgCl_2}=\dfrac{0,2.95}{204,4}.100\approx9,295\%\\ d.V_{ddHCl}=\dfrac{200}{1,05}=\dfrac{4000}{21}\left(ml\right)=\dfrac{4}{21}\left(l\right)\\ C_{MddHCl}=\dfrac{0,4}{\dfrac{4}{21}}=2,1\left(M\right)\)

\(a.n_{CO_2}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\\ a.Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3+H_2O\\ 0,25.......0,25............0,25..........0,25\left(mol\right)\\ C_{MddCa\left(OH\right)_2}=\dfrac{0,25}{0,1}=2,5\left(M\right)\\ b.m_{\downarrow}=m_{CaCO_3}=100.0,25=25\left(g\right)\)

a, Ta có: \(n_{CO_2}=\dfrac{0,84}{22,4}=0,0375\left(mol\right)\)

PT: \(CO_2+2KOH\rightarrow K_2CO_3+H_2O\)

\(n_{K_2CO_3}=n_{CO_2}=0,0375\left(mol\right)\)

\(\Rightarrow m_{K_2CO_3}=0,0375.138=5,175\left(g\right)\)

b, \(n_{KOH}=2n_{CO_2}=0,075\left(mol\right)\)

\(\Rightarrow C_{M_{KOH}}=\dfrac{0,075}{0,2}=0,375\left(M\right)\)

Oh! Thank you! "Khanh Dan"