The correct option is A a - r, t
b - p
c - q, s
d - s
Point to remember:
⇒For Strong Acid+Strong Base, heat of neutralisation is always equal to –13.7kcal/mole or –57.1kJ/mole.
⇒ For any other combination it must be less than –13.7kcal/mole or –57.1kJ/mole.
⇒ Rest of energy utilised for ionisation of weak acid or base
Both are strong so ΔH=13.7 kcal
HF1 mole+NaOH1 mole
HF weak acid thus ΔH≤13.7 kcal
weak base and strong acid so ΔH≤13.7 kcal
two mole of [H+] reacting with two mole of [OH−] so ΔH=27.4 kcal
both are weak acid so ΔH≤13.7 kcal