posted by Anonymous .
Which of the following is an exothermic process?
condensation of water vapor
mixing ammonium thiocyanate and barium hydroxide and witnessing a temperature drop
I'm torn between ice melting and the last one.
You must add heat to melt ice? right? So that makes it endothermic. You must add heat to boil soup and evaporate water. That makes them endothermic. If you ADD heat to vaporize water, then heat is released when water vapor condenses; therefore, this must be exothermic.