7. If, during the experiment, some water vapour had become trapped in the beaker and did not evaporate (condense on the side of the beaker), how could this have affected the experimental results?

If water vapor became trapped and didn't evaporate, it would affect the experimental results by making the calculated mass of evaporated water *lower* than the actual value. Here's why:<br /><br />The experiment likely involves determining the mass of water evaporated by measuring the mass difference of the beaker before and after evaporation. If some water condenses on the sides of the beaker, that condensed water is still present in the "after" measurement. Therefore, the measured mass loss (attributed to evaporation) would be smaller than the true amount of water that transitioned to vapor.<br />