Pressure is a measure of force expressed in force per unit of area. The basic SI unit of pressure is expressed in kilograms per square meter or Pascal. Explain how the pressure of compressed air in a SCBA storage cylinder is commonly monitored? Is there a difference between gauge pressure and absolute pressure? Why, or why not? What does it mean when the gauge on the SCBA is at 0? Your response must be at least 200 words in length.

Part of this unit concentrated on gaseous molecules, but stated that liquids and solids can also consist of molecules. Ethanol and aqueous film-forming foam are examples of liquid molecules. Discuss how the thickness (viscosity) of ethanol or aqueous film forming foams can be changed. Does the foam have a higher or lower molecular weight? Why, or why not? Your response must be at least 200 words in length.