What is the best temperature water for rinsing dishes? I've googled this question, and gotten many answers, very few of which have any rational basis for them whatsoever. For example, some people say that it's better to use hot water, because the soap dissolves better in hot water. However, it's not at all clear to me that dissolving is the underlying mechanism for getting rid of the soap, and none of the answers I've seen (including here on PF) speak to that. Before I go on, let me say that quickness of drying is not on my radar screen here. I totally recognize that hot water, having more highly excited molecules, will evaporate quicker than cool water, given the same environment. I do know this: if I have just emptied a bowl of soapy water into my sink, and I'm trying to rinse the soap down the drain, cool water seems to work much faster than hot. Indeed, hot water seems to make a lot more suds than cool water. So, first: what is the underlying mechanism by which water removes soap? Is is sheer mechanical action, where the water simply displaces the soap out of the way? Or is it chemical (dissolving)? Second: what temperature water would make this underlying mechanism work faster? Third: Suppose the answer to my Second Part is cool water. What guarantee would I have that there isn't a soap residue left on my dishes? My second main question is this: is the efficacy of soap (that is, its ability to remove dirt) at all related to the amount of suds present? I hope that I have put this thread in the right place. My apologies if not. I am not a chemist, so please aim your explanations accordingly. Thank you!