A car mechanic had a sealed bucket containing a substance in the gas phase. She left the bucket outside over the weekend. When she returned, the substance had changed phase, and the substance was in the liquid phase. What happened to the molecules of this substance?

relative humidity, temperature and dew point -- are bound together in the mathematical relationship below. relative humidity changes when temperatures change. because warm air can hold more water vapor than cool air, relative humidity falls when the temperature rises if no moisture is added to the air. so i would say a

the endomembrane system i think