A) 500. j of work are done on a system in a process that decreases the system’s thermal energy by 200. j. how much energy is transferred as heat? is the transfer into the system or out of thesystem? (b) what is the heat transfer if the system’s internal energy instead increases by 200. j? into or out of the system?

The First Law of Thermodynamics relates internal energy or thermal energy, heat and work. There are some important things to consider. The first law will not tell you the amount of internal or thermal energy, but only how much it has changed. Heat is not temperature. Heat is the flow of energy from hot to cold objects. If heat flows into a system, we consider it positive. If heat flows out of a system, we consider it negative. Work can be done on or by the gas. If the volume increases, the gas is doing the work and we consider this negative. If work is done on the gas, the volume decreases and we consider this positive.