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.
Answer:
2.The cooling effects of more indirect sunlight cause autumn and winter. Because of the Earth's approximately 23.5º tilt, the seasons in the Northern and Southern Hemispheres are reversed, about six months apart from each other.
3.In North America, around June 21, Earth tilts on its axis toward the Sun. That means that at the northern summer solstice, North America will experience summer, and winter will start in in the Southern Hemisphere. Winter Solstice. Around December 21, the Northern Hemisphere tilts the farthest away from the Sun.
Explanation: