Answer :
Final answer:
The correct option is a) use a dry paper towel. To handle a hot beaker or flask, the best method is using a dry paper towel folded into a holder or beaker tongs for a secure hold. It is crucial to ensure that the paper towel holder does not contact the liquid, and hot glassware should never be touched with bare hands. Utilizing non-conductive surfaces and covering flasks with an inverted beaker can also help regulate temperature.
Explanation:
The correct option is a) use a dry paper towel. To handle hot objects like a beaker or evaporating dish correctly in a laboratory, it is important to use the proper tools and techniques to ensure safety. While handling hot beakers or flasks, using a dry paper towel folded several times to create a paper towel holder can serve as an insulating grip.
This paper towel holder should be wrapped around the top of the beaker or flask but should be positioned in such a way that it does not come into contact with the hot liquid being poured, which would cause the paper to wet and weaken. It is also suggested to use beaker tongs for a more secure hold.
Additionally, placing the hot flask on non-conductive surfaces such as a folded paper towel, wood block, or cork ring can help maintain the temperature of the hot liquid. It is essential to avoid using wet towels or holding hot glassware with bare hands to prevent burns and accidents.
When pouring boiling solutions, such as during hot filtering, ensure that you pour in portions to avoid overheating the paper towel holder. Another key point is to avoid touching the hot flask directly with your hands; use the paper towel holder or beaker tongs. Furthermore, when dealing with solutions that cool quickly like those using solvents with low boiling points, it may be beneficial to cover the flask with an inverted beaker to create an insulating atmosphere.