Heat liberated from reaction =40×10−3×57×103JHeat gained by solution =mC∆T m= mass of solution =V×d=1000×1 =1000g Heat gained by solution =1000×4.2×∆T... (2) From (1) and (2) Heat liberated = Heat gained 40×10−3×57×103=1000×4.2×∆T ∆T=54×10−2∘C (Rounded off to the nearest integer)