Answer:
[tex]\large \boxed{\text{0.022 mol/L}}[/tex]
Explanation:
1. Balanced chemical equation.
[tex]\rm HCl + NaOH \longrightarrow \, NaCl + H_{2}O[/tex]
2. Moles of NaOH
[tex]\text{Moles of NaOH} =\text{ 17.6 mL NaOH} \times \dfrac{\text{0.025 mmol NaOH }}{\text{1 mL NaOH }} = \text{0.440 mmol NaOH }[/tex]
3. Moles of HBr
The molar ratio is 1 mmol HCl:1 mmol NaOH
[tex]\text{Moles of HCl}= \text{0.440 mmol NaOH} \times \dfrac{\text{1 mmol HCl}}{\text{1 mmol NaOH}} =\text{0.440 mmol HCl}[/tex]
4. [HCl]
[tex]\text{[HCl]} = \dfrac{\text{0.440 mmol HCl}}{\text{20.0 mL HCl}} = \textbf{0.022 mol/L}\\\text{The concentration of HCl is $\large \boxed{\textbf{0.022 mol/L}}$}[/tex]}
