30ml = 0,03l

70ml = 0,07l

\(n_{CaCl2}=0,5.0,03=0,015\left(mol\right)\)

\(n_{AgNO3}=1.0,07=0,07\left(mol\right)\)

Pt : \(CaCl_2+2AgNO_3\rightarrow Ca\left(NO_3\right)_2+2AgCl|\)

           1              2                 1                    2

      0,015         0,07             0,015             0,03

Lập tỉ số so sánh : \(\dfrac{0,015}{1}< \dfrac{0,07}{2}\)

                 ⇒ CaCl₂ phản ứng hết , AgNO₃ dư

                ⇒ Tính toán dựa vào số mol của CaCl₂ 

\(n_{AgCl}=\dfrac{0,015.2}{1}=0,03\left(mol\right)\)

⇒ \(m_{AgCl}=0,03.143,5=4,305\left(g\right)\)

\(n_{Ca\left(NO3\right)2}=\dfrac{0,03.1}{2}=0,015\left(mol\right)\)

\(n_{AgNO3\left(dư\right)}=0,07-\left(0,015.2\right)=0,04\left(mol\right)\)

Sau phản ứng : 

\(V_{dd}=0,03+0,07=0,1\left(l\right)\)

\(C_{M_{Ca\left(NO3\right)2}}=\dfrac{0,015}{0,1}=0,15\left(M\right)\)

\(C_{M_{AgNO3\left(dư\right)}}=\dfrac{0,04}{0,1}=0,4\left(M\right)\)

 Chúc bạn học tốt

\(n_{Ca^{2+}}=0.1\cdot0.4=0.04\left(mol\right),n_{Ba^{2+}}=0.1\cdot0.2=0.02\left(mol\right)\)

\(n_{CO_3^{2-}}=0.2\cdot0.3+0.2\cdot0.1=0.08\left(mol\right)\)

\(Ca^{2+}+CO_3^{2-}\rightarrow CaCO_3\)

\(0.04.......0.04.......0.04\)

\(Ba^{2+}+CO_3^{2-}\rightarrow BaCO_3\)

\(0.02.......0.02.......0.02\)

\(m_{\downarrow}=0.04\cdot100+0.02\cdot197=7.94\left(g\right)\)

a)
$BaCl_2 + Na_2SO_4 \to BaSO_4 + 2NaCl$

$n_{BaCl_2} = 0,01 = n_{Na_2SO_4} = 0,01 \Rightarrow $ Vừa đủ

$n_{BaSO_4} = n_{Na_2SO_4} = 0,01(mol)$
$m_{BaSO_4} = 0,01.233 = 0,233(gam)$
b)

$n_{NaCl} = 2n_{Na_2SO_4} = 0,02(mol)$
$V_{dd} = 0,1 + 0,2 = 0,3(lít)$
$C_{M_{NaCl}} = \dfrac{0,02}{0,3} = 0,067M$

c)

$[Na^+] = [Cl^-] = C_{M_{NaCl}} = 0,067M$

\(n_{BaCl_2}=0.1\cdot0.1=0.01\left(mol\right)\)

\(n_{Na_2SO_4}=0.2\cdot0.05=0.01\left(mol\right)\)

\(BaCl_2+Na_2SO_4\rightarrow BaSO_4+2NaCl\)

\(0.01..........0.01............0.01..............0.02\)

\(m_{BaSO_4}=0.01\cdot233=2.33\left(g\right)\)

\(C_{M_{NaCl}}=\dfrac{0.01}{0.1+0.2}=0.03\left(M\right)\)

\(\left[Na^+\right]=\left[Cl^-\right]=0.03\left(M\right)\)

$n_{Ba^{2+}} = 0,1.0,5 = 0,05 < n_{SO_4^{2-}} = 0,1$ nên $SO_4^{2-}$ dư

$n_{BaSO_4} = n_{Ba^{2+}} = 0,05(mol)$
$m_{BaSO_4} = 0,05.233 = 11,65(gam)$

$n_{OH^-} = 0,1.0,5.2 + 0,1.0,5 = 0,15(mol)$
$n_{H^+} = 0,1.2 = 0,2(mol)$

$H^+ + OH^- \to H_2O$

$n_{H^+\ dư} = 0,2 - 0,15 = 0,05(mol)$

$V_{dd} = 0,1 + 0,1 + 0,1 = 0,3(lít)$

$[H^+] = \dfrac{0,05}{0,3} = \dfrac{1}{6}M$
$pH = -log( \dfrac{1}{6} ) = 0,778$

\(n_{Ba^{2+}}=0.1\cdot0.5=0.05\left(mol\right)\)

\(n_{OH^-}=0.1\cdot0.5\cdot2+0.1\cdot0.5=0.15\left(mol\right)\)

\(n_{H^+}=2\cdot0.1\cdot1=0.2\left(mol\right)\)

\(n_{SO_4^{2-}}=0.1\left(mol\right)\)

\(Ba^{2+}+SO_4^{2-}\rightarrow BaSO_4\)

\(0.05.........0.05.............0.05\)

\(SO_4^{2-}dư\)

\(m_{\downarrow}=0.05\cdot233=11.65\left(g\right)\)

\(H^++OH^-\rightarrow H_2O\)

\(0.15.......0.15\)

\(n_{H^+\left(dư\right)}=0.2-0.15=0.05\left(mol\right)\)

\(\left[H^+\right]=\dfrac{0.05}{0.1+0.1+0.1}=\dfrac{1}{6}\)

\(pH=-log\left(\dfrac{1}{6}\right)=0.77\)

Na₂SO₄ + BaCl₂ 2NaCl + BaSO₄

n_Na2SO4=0,05.0,1=0,005(mol)

n_BaCl2=0,1.0,1=0,01(mol)

Vì 0,005<0,01 nên BaCl₂ dư 0,005(mol)

Theo PTHH ta có;

n_Na2SO4=n_BaSO4=0,005(mol)

2n_Na2SO4=n_NaCl=0,01(mol)

m_BaSO4=0,005.233=1,165(g)

C_M dd BaCl₂=\(\dfrac{0,01}{0,15}=115\)M

a)PTHH: \(Ba\left(OH\right)+Na_2CO_3\rightarrow2NaOH+BaCO_3\downarrow\)

             \(BaCO_3\underrightarrow{t^o}BaO+CO_2\uparrow\)

Ta có: \(n_{Ba\left(OH\right)_2}=0,4\cdot0,2=0,08\left(mol\right)\)

\(\Rightarrow n_{NaOH}=0,16mol\) \(\Rightarrow C_{M_{NaOH}}=\dfrac{0,16}{0,4}=0,4\left(M\right)\) (Coi V_dd thay đổi không đáng kể)

b) Theo PTHH: \(n_{BaCO_3}=n_{Ba\left(OH\right)_2}=n_{BaO}=0,08mol\) \(\Rightarrow m_{BaO}=0,08\cdot153=12,24\left(g\right)\)

a. Ba(OH)₂ +Na₂CO₃ ➝ BaCO₃ + 2NaOH

BaCO₃ ➝ BaO + CO₂

nBa(OH)₂ = 0,08 mol

=> nNaOH = 2nBa(OH)₂ = 0,16 mol

=> C_M = 0,4 M

b) Bảo toàn Ba: nBaO = nBa(OH)₂ = 0,08 mol

=> m = 12,24 g

a)\(n_{CuSO_4}=0,4.0,5=0,2\left(mol\right)\)

\(PTHH:CuSO_4+2NaOH\rightarrow Cu\left(OH\right)_2+Na_2SO_4\)

Mol:               0,2                0,4                   0,2

⇒ \(m_{Cu\left(OH\right)_2}=0,2.98=19,6\left(g\right)\)

b)\(C_{M\left(ddNaOH\right)}=\dfrac{0,4}{0,3}=1,3\left(M\right)\)

c)\(PTHH:Cu\left(OH\right)_2\underrightarrow{t^o}CuO+H_2O\)

Mol:                 0,2                   0,2

=> m_CuO = 0,2.80 = 16 (g)