Câu 5: Theo gt ta có: $n_{AgNO_3}=0,075(mol);n_{NaCl}=0,1(mol)$
$Ag^++Cl^-\rightarrow AgCl$
$[NO_3^-]=0,375M;[Na^+]=0,5M;[Cl^-]=0,125M$
Câu 6: Theo gt ta có: $n_{BaCl_2}=0,02(mol);n_{Na_2SO_4}=0,06(mol)$
$Ba^{2+}+SO_4^{2-}\rightarrow BaSO_4$
$\Rightarrow [Cl^-]=0,08M;[Na^+]=0,24M;[SO_4^{2-}]=0,08M$
Câu 7:
a, Ta có: $n_{NaOH}=0,0009(mol);n_{HCl}=0,0006(mol)$
$H^++OH^-\rightarrow H_2O$
$\Rightarrow pH=12,48$
b, Ta có: $n_{Ba(OH)_2}=0,0001(mol);n_{H_2SO_4}=0,00032(mol)$
$OH^-+H^+\rightarrow H_2O$
$\Rightarrow pH=2,36$