As a new Assistant Engineer in AAMJ Sdn Bhd, Mr. Alif was asked by his Principal Engineer to do a few studies to improve his knowledge on mixing and heating processes. One of the studies is described below: 10 kmol/hr of steam at 300 oC, 100 kmol/hr gas mixture with 50 mol% CO, 30 mol% H2 and 20 mol% O2 gas at 100 oC and 10 kmol/hr of atmospheric air containing 10 mol% water vapor at 25 oC are mixed in a heated mixing tank to 500 oC. The operating pressure of the system is 1.01325 bar (absolute).