Câu 1:

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

Ta có: \(n_{HCl}=0,2\cdot2=0,4\left(mol\right)=n_{NaOH}\)

\(\Rightarrow C_{M_{NaOH}}=\dfrac{0,4}{0,2}=2\left(M\right)\)

Câu 2: Bạn xem lại đề !!

Câu 2:

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

Ta có: \(n_{NaOH}=\dfrac{200\cdot10\%}{40}=0,5\left(mol\right)=n_{HCl}\)

\(\Rightarrow m_{ddHCl}=\dfrac{0,5\cdot36,5}{3,65\%}=500\left(g\right)\)

Câu 3:

\(NaHCO_3+HCl\rightarrow NaCl+H_2O+CO_2\uparrow\)

\(Ca\left(OH\right)_2+HCl\rightarrow CaCl_2+H_2O\)

\(Na_2CO_3+2HCl\rightarrow2NaCl+H_2O+CO_2\uparrow\)

\(Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)

\(Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\)

*Các chất trên tác dụng tương tự với H₂SO₄ loãng 

Bonus:  \(Ba\left(NO_3\right)_2+H_2SO_4\rightarrow BaSO_4\downarrow+2HNO_3\)

bôi đen chi zợ, bôi trắng ik pn

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)

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

nCaO=0,4 mol

mH2O=1g=>nH2O=1/18mol

PTHH: CaO+H2O=> Ca(OH)2

               0,4:1/18 => nCaO dư theo nH2O

Cm=1/18:1=1/18M

a.250ml=0,25l ; nHCl=0,25.1,5=0,375mol

KOH+HCl->KCl+H2O

1mol 1mol 1mol

0,375 0,375 0,375

VKOh=0,375/2=0,1875l

b.CM KCL=0,375/0,25=1,5M

c.NaOH+HCL=NaCl+H2O

1mol 1mol

0,375 0,375

mdd NaOH=0,375.40.100/10=150g

n_HCl = C_M . V = 1,5 . 0,25 = 0,375 mol

PTHH: KOH + HCl -------> KCl + H₂O

Pt: 1 1 1 1 (mol)

Pư 0,375 <-0,375 -----> 0,375-> 0,375 (mol)

a) V_KOH = \(\dfrac{n}{C_M}\)= 0,1875 l

b) C_M KCl = \(\dfrac{n}{V}\)= \(\dfrac{0,375}{0,25+0,1875}\)\(\approx\)0,86 M

c) PTHH: NaOH + HCL ----> NaCl + H₂O

Pt: 1 1 1 1 (mol)

Pư 0,375 <- 0,375 ------>0,375 --> 0,375 (mol)

m_ctNaOH = n . M = 15 g

m_{ddNaOH = \(\dfrac{15.100\%}{10\%}\)=} 150 g

:3

\(Fe_2O_3 + 6HCl \rightarrow 2FeCl_3 + 3H_2O\)

\(CuO + 2HCl \rightarrow CuCl_2 + H_2O\)

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

\(n_{NaOH} = 0,2 . 1 = 0,2 mol\)

\(n_{HCl dư} = n_{NaOH}= 0,2 mol\)

\(\Rightarrow n_{HCl pư}= n_{HCl ban đầu} - n_{HCl dư}= 1,4- 0,2 = 1,2 mol\)

Gọi n_{\(Fe_2O_3\)} và n_\(CuO\) là x, y

\(\begin{cases} 160x + 80y=40\\ 6x + 2y= 1,2 \end{cases} \)

\(\begin{cases} x=0,1\\ y=0,3 \end{cases} \)

\(\Rightarrow m_{Fe_2O_3}= 0,1 . 160= 16g\)

\(m_{CuO} = 0,3 . 80=24g\)

\(m_{HCl}=\dfrac{300.7,3\%}{100\%}=21,9g\\ n_{HCl}=\dfrac{21,9}{36,5}=0,6mol\\ HCl+NaOH\rightarrow NaCl+H_2O\left(1\right)\\ n_{NaOH\left(1\right)}=n_{HCl}=0,6mol\\ m_{H_2SO_4}=\dfrac{200.9,8\%}{100\%}=19,6g\\ n_{H_2SO_4}=\dfrac{19,6}{98}=0,2mol\\ H_2SO_4+2NaOH\rightarrow Na_2SO_4+2H_2O\left(2\right)\\ n_{NaOH\left(2\right)}=0,2.2=0,4mol\\ n_{NaOH}=0,4+0,6=1mol\\ m_{NaOH}=1.40=40g\\ m_{ddNaOH}=\dfrac{40}{5\%}\cdot100\%=800g\)