Does it really work to use the hose to heat water in a bucket? I do not want to leave my windows open at night for the hose to go outside. I have heard the hot air from the portable air conditioner can be disposed of in this way.
This won't work in that simplified form. Even if the water did absorb a bit of heat as the air passed through, the water would heat up fairly quickly, at which point it would stop absorbing heat from the air. "Dissipation" doesn't mean "disappeared". The heat still exists somewhere. You'd have to change the water regularly. Also, you'd be adding moisture to the air via evaporation and possibly effervescence, countering the cooling effect of the air conditioner.
Now, if you wanted to split the airflow into many tiny tubes, provide a large quantity of cold water, and change the water regularly, it could work. Maybe. But probably not very well.