At a particular temperature H+(aq) + OH−(aq) → H2O(l); ΔH = −57.1kJ. The approximate heat evolved when 400 mL of 0.2 H2SO4 is mixed with 600 mL of 0.1 m KOH solution will be:
3.42kJ
Number of equivalent H2SO4 taken
= 0.2 × 2 × 4001000 = 0.16
Number of equivalent KOH added
= 600 × 0.11000 = 0.06
Number of equivalent of acid and bases which neutralized each other = 0.06
∴ heat evolved = 0.06 × 57.1 kJ = 3.426 kJ