/sci/ - Science & Math

Sup /sci/ I have a dilemma for a physicist or engineer. At work (I'm a microbiologist) we have a problem with contamination in one type of our biological media (SDA). We've looked into it and it doesn't appear that our water baths or incubators are to blame, which leaves technique or insufficient sterilization to blame for the source. I know my technique is sound, but my lab supervisor refuses to believe that our autoclave could be the source. Here's the dilemma:

To sterilize the media it needs to reach 121 degrees C for 15 minutes (It's also under several atmospheres of pressure to prevent boiling. It also has a max liquid capacity of 9 liters). I'm fairly certain our autoclave was calibrated either using water or an empty chamber. My logic is that if it's calibrated to reach 121 degrees for 9 liters of water, if we try to autoclave 9 liters of media (the media is very dense and has a higher heat capacity than the water does) it will not reach the desired temperature by the end of the cycle (15 minutes). What I'm asking for is an engineer/physicist or somebody who knows thermodynamics to give me some good, easy equations to use to show my supervisor the difference between heating water and heating a denser, more viscous liquid.

tl;dr I need to show somebody the difference between heating water and heating a liquid with a different heat capacity.