\(a/n_{HNO_3}=0,02.1=0,02mol\\ HNO_3+NaOH\rightarrow NaNO_3+H_2O\\ n_{NaOH}=n_{NaOH}=n_{NaNO_3}=0,02mol\\ m_{ddNaOH}=\dfrac{0,02.40}{4\%}\cdot100\%=20g\\ b/m_{ddHNO_3}=20.1,12=22,4g\\ C_{\%NaNO_3}=\dfrac{0,02.85}{22,4+20}\cdot100\%\approx4,01\%\)

\(n_{H_2SO_4}=0,1.0,75=0,075mol\\ H_2SO_4+2KOH\rightarrow K_2SO_4+2H_2O\)

0,075           0,15               0,075          0,15

\(a)m_{K_2SO_4}=0,075.175=13,05mol\)

\(b)H_2SO_4+2NaOH\rightarrow Na_2SO_4+2H_2O\\ n_{NaOH}=0,075.2=0,15mol\\ m_{ddNaOH}=\dfrac{0,15.40}{15\%}\cdot100\%=40g\\ V_{ddNaOH}=\dfrac{40}{1,05}=38,1ml\)      

\(n_{NaOH}=\dfrac{40.20\%}{100\%}:40=0,2\left(mol\right)\)

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

0,2------>0,1-------->0,1

\(m_{ddH_2SO_4}=\dfrac{0,1.98.100\%}{25\%}=39,2\left(g\right)\)

\(m_{Na_2SO_4}=0,1.142=14,2\left(g\right)\)

bôi đen chi zợ, bôi trắng ik pn

\(n_{HCl}=0,6\cdot1=0,6\left(mol\right)\)

\(NaOH+HCl\rightarrow NaCl+H_2O\)

                 0,6         0,6

Để trung hòa:  \(n_{H^+}=n_{OH^-}=n_{HCl}=0,6\left(mol\right)\)

\(\Rightarrow n_{NaOH}=n_{OH^-}=0,6\left(mol\right)\)

\(m_{ctNaOH}=0,6\cdot40=24\left(g\right)\)

\(m_{ddNaOH}=\dfrac{24}{30\%}\cdot100\%=80\left(g\right)\)

\(m_{NaCl}=0,6\cdot58,5=35,1\left(g\right)\)

n H C l = 0 , 6 ⋅ 1 = 0 , 6 ( m o l )

N a O H + H C l → N a C l + H 2 O

                  0,6         0,6

Để trung hòa: n H + = n O H − = n H C l = 0 , 6 ( m o l ) ⇒ n N a O H = n O H − = 0 , 6 ( m o l )

m c t N a O H = 0 , 6 ⋅ 40 = 24 ( g )

m d d N a O H = 24 30 % ⋅ 100 % = 80 ( g )

m N a C l = 0 , 6 ⋅ 58 , 5 = 35 , 1 ( g )

Bài 1

\(a,n_{CuO}=\dfrac{16}{80}=0,2\left(mol\right)\\ CuO+2HCl\xrightarrow[]{}CuCl_2+H_2O\\ n_{CuCl_2}=n_{CuO}=0,2mol\\ m_{CuCl_2}=0,2.135=27\left(g\right)\\ b.n_{HCl}=0,2.2=0,4\left(mol\right)\\ C_{MHCl}=\dfrac{0,4}{0,5}=0,8\left(M\right)\)

Bài 5

\(a,n_{NaOH}=0,2.1=0,2\left(mol\right)\\ 2NaOH+H_2SO_4\xrightarrow[]{}Na_2SO_4+2H_2O\\ n_{H_2SO_4}=0,2:2=0,1\left(mol\right)\\ C_{MH_2SO_4}=\dfrac{0,1}{0,4}=0,25\left(M\right)\\ b,n_{Na_2SO_4}=0,2:2=0,1\left(mol\right)\\ C_{MNa_2SO_4}=\dfrac{0,1}{0,2+0,4}=\dfrac{1}{6}\left(M\right)\\ c,m_{Na_2SO_4}=0,1.142=14,2\left(g\right)\)

a,\(n_{NaOH}=0,5.1=0,5\left(mol\right);n_{H_2SO_4}=0,5.1=0,5\left(mol\right)\)

PTHH: 2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O

Mol:        0,5          0,25             0,25

Ta có: \(\dfrac{0,5}{2}< \dfrac{0,5}{1}\) ⇒ NaOH hết, H₂SO₄ dư

\(m_{Na_2SO_4}=142.0,25=35,5\left(g\right)\)

b,\(C_{M_{Na_2SO_4}}=\dfrac{0,25}{1}=0,25M\)

\(C_{M_{H_2SO_4dư}}=\dfrac{0,5-0,25}{1}=0,25M\)

nH2SO4=0,1(mol) 

a) PTHH: 2 NaOH + H2SO4 -> Na2SO4 + 2 H2O

b) 0,2___________0,1________0,1(mol)

mNaOH=0,2.40=8(g)

=>mddNaOH=(8.100)/25= 32(g)

c) mNa2SO4=0,1.142=14,2(g)

d) PTHH: 2 KOH + H2SO4 -> K2SO4 +2 H2O

nKOH=0,2(mol) => mKOH=0,2.56=11,2(g)

=> mddKOH=(11,2.100)/8=140(g)

=> VddKOH= 140/1,085=129,03(ml)

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