How do you make sleeping gas?

Answer 1

You might as well make a poisonous gas; it's easier and it's almost certainly going to turn out the same way in the end anyway. "Sleeping gas" is a staple in certain kinds of fiction: some odorless, colorless gas that causes people to fall deeply asleep and wake up unharmed later. The reality is that any gas that can put people to sleep can also kill them, and the difference in dosage between unconsciousness and death can be surprisingly small. This is why an anesthesiologist monitors the entire surgery when a patient is given a general anesthetic; the dosage needs to be carefully adjusted based on the patient's vital signs at any given moment in order to keep the patient both unconscious and alive.