AP EAMCET202124 Aug 2021Evening ShiftChemistryThermodynamics (C)Actual
For strong acid and strong base neutralisation net chemical change is aligned H ⁺+ OH ⁻ & H ₂ O (l) ; _r H^ & =-55.84 kJmol ⁻¹ . aligned If enthalpy of neutralisation of CH ₃ COOH by NaOH is 49.86 ~kJ ~mol ⁻¹ , then enthalpy of ionisation of CH ₃ COOH is
Options
- A5.98 ~kJ ~mol ⁻¹
- B-5.98 ~kJ ~mol ⁻¹
- C105.7 ~kJ ~mol ⁻¹
- D-59.8 ~kJ ~mol ⁻¹
Correct answer
A. 5.98 ~kJ ~mol ⁻¹
Step-by-step solution
H ⁺+ OH ⁻ H ₂ O ; _r H^ =-55.84 ~kJ / mol H ₂ O H ⁺+ OH ⁻ ; _r H^ =55.84 ~kJ / mol ...(i) CH ₃ COOH + NaOH CH ₃ COONa + H ₂ O _r H=49.86 ...(ii) CH ₃ COOH CH ₃ COO ⁻+ H ⁺ ; H_ i =? Subtracting Eq. (ii) from Eq. (i) H_ i =55.84-49.86=5.98 ~kJ ~mol ⁻¹