HI all
I am not convinced
The reason for the effect given by bersaga is flawed he suggests that hot water holds more disolved gas but infact more gas is held by cold water if the water is near to boiling then there would be not much gas in the water.
when dose the effect kick in. if you compared water at 90c with water at 89c would the 90c water freeze first or if it were a particulary cold frosty day and the cooler water was about 5c which would freeze first. I know which way i would bet
remembre there is per deg C only 4.19j/gramm of water of energy to remove before until the water freezes at around 0c and remember the higher the TD the quicker the heat exchange