To find the concentration of hydrochloric acid (HCl) from the given titration data, we need to use the balanced chemical equation for the neutralization reaction between HCl and sodium hydroxide (NaOH):
\[ \text{HCl} + \text{NaOH} \rightarrow \text{NaCl} + \text{H}_2\text{O} \]
From the equation, we see that HCl and NaOH react in a 1:1 molar ratio.
Given data:
- Volume of NaOH solution = 25 cm³ = 0.025 L
- Concentration of NaOH solution = 0.1 M
- Volume of HCl solution = 15 cm³ = 0.015 L
Step 1: Calculate moles of NaOH
Moles of NaOH can be calculated using the formula: \[ \text{moles of NaOH} = \text{concentration (mol/L)} \times \text{volume (L)} \] \[ \text{moles of NaOH} = 0.1 , \text{mol/L} \times 0.025 , \text{L} = 0.0025 , \text{mol} \]
Step 2: Use the 1:1 ratio to find moles of HCl
Since the reaction ratio of HCl to NaOH is 1:1, the moles of HCl will also be: \[ \text{moles of HCl} = 0.0025 , \text{mol} \]
Step 3: Calculate the concentration of HCl
Now, we can calculate the concentration of HCl using the formula: \[ \text{Concentration (C)} = \frac{\text{moles of solute}}{\text{volume of solution (L)}} \] Given that the volume of HCl solution is 0.015 L: \[ \text{Concentration of HCl} = \frac{0.0025 , \text{mol}}{0.015 , \text{L}} \approx 0.167 , \text{M} \]
Conclusion:
The concentration of the hydrochloric acid (HCl) solution is approximately 0.167 M.