Answer: It is important to wet the filter paper in the Buchner funnel first with cold re crystallization solvent before the re crystallization mixture being filtered to minimize gaps around the edges of the filter paper which can prevent mechanical impurities from passing through. This gives better filtration where most impurities can be filtered. Furthermore, it provides good vacuum.
1. D) 2. I think the correct answer from the choices listed above is option C. The tools that <span>should
be used to record the most complete data about a gas are a manometer
and a thermometer. Pressure and temperature are important measurements
for a gas since from these data we can calculate any other properties of
the gas.</span>