Question

Answer 1

Câu 6.

a) \(n_{Na}=\dfrac{2,3}{23}=0,1\left(mol\right)\)

PTHH: 2Na + 2H₂O → 2NaOH + H₂O

Mol:      0,1                        0,1

 \(\Rightarrow n_{OH^-}=0,1.1=0,1\left(mol\right)\)

 \(\Rightarrow\left[OH^-\right]=\dfrac{0,1}{1}=0,1M\)

  \(\Rightarrow pH=14+log\left(0,1\right)=13\)

b) \(n_{HCl}=\dfrac{5,6}{22,4}=0,25\left(mol\right)\Rightarrow n_{H^+}=0,25.1=0,25\left(mol\right)\)

\(\Rightarrow\left[H^+\right]=\dfrac{0,25}{2,5}=0,1M\Rightarrow pH=-log\left(0,1\right)=1\)