Define absolute zero and discuss the atomic and molecular motion which leads to absolute zero. Define it as -273 degree celsius. Kelvin temperatures have no degree designations, they are just listed as Kelvin units. Determine boiling and freezing temperature of water using kelvin units, freezing is 273 K units and boiling is 373 K units. Determine the formula for conversion. K =C(degrees) + 273. Discuss early thoughts regarding heat as an invisible fluid which flows like water. Discuss James Joules demonstration that heat flow was nothing more than a flow of energy. State and discuss the first law of thermodynamics.