We are given the volume of a graduated cylinder and asked for the mass when it is empty. The simplest way to just weight the empty graduated cylinder. If the cylinder is already filled with liquid, simply convert it to mass using its density. Then, weight the full cylinder and subtract the masses.
It starts at the bottom and then it goes up into the air as evaporation and that’s when the air gets cooler so gas is cooler and the liquid would be hotter
