Step 1: Heat lost by calorimeter=mcalScal×30 Heat gained by liq=5×Sliq.50+mL mCalSCal30=Seiq50+5Lf.........(1) Step 2: Heat lost by calorimeter =mcalScal×30 Heat gained by liq =80×Sliq×20 mCalSCal×30=80Sliq20......(2) 1600Sliq−250Sliq=5Lf 1350Slq=5Lf