>> If you take a bowl of ice to its freezing point it will still be entirely frozen. Then if you continue adding energy, it will remain at its freezing point while progressively more of it melts [...] if you are at the freezing point, then all of the energy you add goes to melting the ice (and none of it goes to increasing the temperature), until all of the ice is gone.
> this strikes me as probably wrong? The temperature at the surface has raised, which is how some of the surface ice melted. The temperature on average has to raise because thermodynamics.
What do yo you think is wrong in the quoted passage?
The "temperature on average" of the system described is the temperature of every part of it: the temperature where the liquid and solid phases co-exist. When you heat that system (i.e. add energy) the temperature doesn't have to increase "because of thermodynamics". The ice melts and everything remains at the same temperature. Only when the ice is gone the water starts to warm up.
> this strikes me as probably wrong? The temperature at the surface has raised, which is how some of the surface ice melted. The temperature on average has to raise because thermodynamics.
What do yo you think is wrong in the quoted passage?
The "temperature on average" of the system described is the temperature of every part of it: the temperature where the liquid and solid phases co-exist. When you heat that system (i.e. add energy) the temperature doesn't have to increase "because of thermodynamics". The ice melts and everything remains at the same temperature. Only when the ice is gone the water starts to warm up.