Final answer:
To pour powder into a barrel safely and accurately, one should always use a funnel. This method avoids waste and reduces the risk of accidental ignition, making it essential for handling combustible powders.
Step-by-step explanation:
You should always use a funnel to pour powder into the barrel. This question seems to be related to loading a muzzle-loading firearm or a similar process where you need to transfer powder into a container with precision and safety. The use of a funnel ensures that the powder does not spill or create a mess, which could be both wasteful and dangerous, especially if the powder is combustible. Moreover, by using a funnel, you can avoid static discharge, which could ignite the powder.
The reference information provided discusses the dispersion of gas and the input of energy required for molecular separation which is unrelated to the student's question about pouring powder into a barrel. However, it highlights the importance of understanding the physical processes and safety precautions when dealing with substances that need to be measured and transferred accurately and safely.