Verified Solution • 2025–26 Session
moderate
QJEEAdv15Ch1542: JEE Advanced 2015 Chemistry - Class 11 JEEAdv15Ch1542 Solution: Paragraph When 100 mL of 1.0 M KCl was mixed with 100 mL of 1.0 …
Paragraph
When 100 mL of 1.0 M KCl was mixed with 100 mL of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of 5.7o C was measured for the beaker and its contents (Expt. 1). Because the enthalpy of neutralization of a strong acid with a strong base is constant (-57.0 kJ/mol), this experiment could be used to measure the calorimeter constant. In a second experiment (Expt. 2) 100 mL of 2.0 M acetic acid (Ka = 2.0 10-5) was mixed with 100 mL of 1.0 M NaOH (under identical conditions to Expt. 1) where a temperature rise of 5.6o C was measured. (Consider heat capacity of all solutions as 4.2 J/gK and density of all solutions as 1.0 g m/L)
Question
The pH of the solution after Expt. 2 is
When 100 mL of 1.0 M KCl was mixed with 100 mL of 1.0 M NaOH in an insulated beaker at constant pressure, a temperature increase of 5.7o C was measured for the beaker and its contents (Expt. 1). Because the enthalpy of neutralization of a strong acid with a strong base is constant (-57.0 kJ/mol), this experiment could be used to measure the calorimeter constant. In a second experiment (Expt. 2) 100 mL of 2.0 M acetic acid (Ka = 2.0
Question
The pH of the solution after Expt. 2 is
Multiple Choice Options
- A 2.8
- B 4.7
- C 5
- D 7
Step-by-Step Verified Solution
In Expt. 2, the final solution is a buffer as it contains equimolar amounts of acid and salt.
Substituting the values in Eq. (1), we get