\(n_{HCl}=C_M.V=0,5.0,25=0,125\left(mol\right)\)

\(n_{NaOH}=0,5.0,2=0,1\left(mol\right);n_{HCl}=0,5.0,3=0,15\left(mol\right)\)

PTHH: NaOH + HCl → NaCl + H₂O

Mol:        0,1      0,1         0,1

Ta có: \(\dfrac{0,1}{1}< \dfrac{0,15}{1}\) ⇒ NaOH hết, HCl dư

V_{dd sau pứ} = 0,2 + 0,3 = 0,5 (l)

\(C_{M_{ddNaCl}}=\dfrac{0,1}{0,5}=0,2M\)

\(C_{M_{ddHCldư}}=\dfrac{0,15-0,1}{0,5}=0,1M\)

a) nNaCl = 1.0,5 = 0,5 (mol) → mNaCl = 0,5.(23 +35,5) = 29,25 (g)

b) nKNO3 = 2.0,5 = 1 (mol) → mKNO3 = 1.101 = 101 (g)

c) nCaCl2 = 0,1.0,25 = 0,025 (mol) → mCaCl2 = 0,025(40 + 71) = 2,775 (g)

d) nNa2SO4 = 0,3.2 = 0,6 (mol) → mNa2SO4 = 0,6.142 = 85,2 (g)

\(n_{HCl}=0,3.0,8=0,24\left(mol\right)\)

C_M (mol/l) chứ nhỉ đề cho mol rồi mà

\(a,C_{M\left(NaOH\right)}=\dfrac{n}{V}=\dfrac{0,2}{0,2}=1M\\ b,n_{HCl}=\dfrac{7,3}{36,5}=0,2\left(mol\right)\\ C_{M\left(HCl\right)}=\dfrac{n}{V}=\dfrac{0,2}{0,5}=0,4M\\ c,n_{NH_3}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\\ C_{M\left(NH_3\right)}=\dfrac{0,3}{0,3}=1M\\ d,n_{H_2SO_4}=\dfrac{4,9}{98}=0,05\left(mol\right)\\ C_{M\left(H_2SO_4\right)}=\dfrac{0,05}{0,25}=0,2M\)

1: NaOH+HCl->NaCl+H2O

0,375        0,375

\(V_{HCl}=0.375\cdot22.4=8.4\left(lít\right)\)

\(C_{M\left(NaCl\right)}=\dfrac{0.375}{8.4+0.25}=\dfrac{15}{346}\)

\(n_{NaOH}=1,5.0,25=0,375\left(mol\right)\)

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

a) Theo Pt : \(n_{NaOH}=n_{HCl}=n_{NaCl}=0,375\left(mol\right)\)

\(V_{ddHCl}-\dfrac{0,375}{1,5}=0,25\left(l\right)\)

b) \(C_{MNaCl}=\dfrac{0,375}{0,25}=1,5\left(M\right)\)

 Chúc bạn học tốt 

\(a.n_{NaOH}=1,5.0,25=0,375mol\\ NaOH+HCl\rightarrow NaCl+H_2O\\ n_{NaOH}=n_{HCl}=n_{NaCl}=0,375mol\\ V_{HCl}=\dfrac{0,375}{1,5}=0,25l\\ b.C_{M\left(NaCl\right)}=\dfrac{0,375}{0,25+0,25}=0,75M\)