In pharmaceutical manufacturing, chemical reactions are carefully monitored and extremely sensitive. Due to this, equipment to be used must be sterilized to kill all microorganisms to avoid contamination. The most commonly used sterilization method for equipment is steam sterilization. This is typically done by introducing the equipment to be sterilized into an autoclave with rigid volume in which 121 °C steam is introduced for 12 minutes. Some autoclaves have ability to heat up to 140 °C which gives a much lower cleansing time necessary to complete steam sterilization (0.9 minutes). While the sterilization time is attractive for higher temperatures it is important to take into account the amount of energy necessary during start-upto bring the system up to a higher temperature. a) What is the excess enthalpy change required to bring the system from ambient conditionsto 140 °C and 37.7 psig using the ideal gas equation of state? b) What is this enthalpy change using a real gas equation of state? Compare values and explain what it tells you about the system? d) Compare all your values to the steam table. What do you conclude?

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