draw titration ph curve for: (a) 25 ml 0.1 m naoh with 0.1 m hcl

Answer 1

To draw the pH titration curve for the neutralization of 25 mL of 0.1 M NaOH (a strong base) with 0.1 M HCl (a strong acid), we can follow these steps and outline the expected appearance of the curve:

Key Points to Consider:

1. Initial pH of the Strong Base (NaOH):

   • The initial solution contains only NaOH. The pH can be calculated using the formula: \[ \text{pH} = 14 - \text{pOH} = 14 - (-\log[0.1]) = 14 - 1 = 13 \]
   • Initial pH = 13.0.

2. Volume of HCl Added:

   • The titration starts with no added acid. As we add HCl, the pH will start to decrease.

3. Equivalence Point:

   • At the equivalence point, all the NaOH has reacted with HCl.
   • The volume of HCl needed to reach the equivalence point is equal to the amount of NaOH originally present:
     • \( C_1V_1 = C_2V_2 \)
     • \( (0.1 , \text{M})(25 , \text{mL}) = (0.1 , \text{M})(V_2) \)
     • \( V_2 = 25 , \text{mL} \)
   • The pH at the equivalence point is neutral, around pH = 7.0.

4. After the Equivalence Point:

   • Beyond the equivalence point, the solution will consist of excess HCl and the pH will drop further. The pH can be calculated based on the excess concentration of HCl after reaching the equivalence point.

5. Shape of the Curve:

   • The pH curve will start at pH 13.0, decrease gradually at first as HCl is added, then drop sharply around the equivalence point (25 mL), and finally level off at a lower pH due to excess HCl.

Summary of pH Curve Behavior:

• 0 mL HCl: pH = 13 (initial)
• 25 mL HCl: pH = 7 (equivalence point)
• 50 mL HCl: pH drops to around 1 (after equivalence point)

Titration Curve Visual Representation:

To create the titration curve visually, you would see a gradual decrease in pH as you approach 25 mL of HCl added, with a sharp drop around the equivalence point (25 mL), then leveling off at a low pH after the equivalence point.

If you were to sketch this on graph paper:

• The x-axis would represent the volume of HCl added (0 to 50 mL).
• The y-axis would represent pH (0 to 14).
• You would start at (0 mL, pH 13), sharply drop around (25 mL, pH 7), and then level off to a low pH after the equivalence point.

If you want a specific graphical representation, consider using graphing software or tools to plot this data based on the described behavior.