My guess is probably a lot given those wooden doors.

I don't see why this isn't a reasonable question for a chem exam. Maybe you chem guys can give us some insight. Here's the backstory and the question itself:

A chemistry professor whose exam question asked students to calculate the lethal dose of a poisonous gas used in Nazi gas chambers during the Holocaust has taken a leave of absence. Middlebury College in Vermont said that it's investigating under the terms of its faculty misconduct policy.

'This inexplicable failure of judgment trivializes one of the most horrific events in world history, violates core institutional values, and simply has no place on our campus,' wrote Middlebury President Laurie Patton last week. 'We expect our faculty to teach and lead with thoughtfulness, good judgment, and maturity. To say we have fallen short in this instance is an understatement.'

The question posed by Byers asked students to calculate how much poison it would take for them to create a lethal dose of hydrogen cyanide, the deadly chemical mixture used on Jewish people in the Nazi gas chambers during the Holocaust. 'Hydrogen cyanide is a poisonous gas, which Nazi Germany used to horrific ends during The Holocaust,' Byers wrote, according to Middlebury Campus.

'The lethal dose for humans is approximately 300. mg of HCN gas per kilogram of air when inhaled... If a room measured [redacted] ft. what mass of air would it have in g if the density fo the air [redacted] [Celsius] (room temperature) is [redacted]?' The exam also instructed students to, 'Calculate the g of HCN that would give a lethal dose in the above room.'

Archived Daily Fail article

Non-archivable local Faux News article

Archived CBS Jews article

Zyklon B was more expensive to make than crating in a more pure form of hydrogen cyanide(s). And even hydrogen cyanide in pellet form is not something anyone would legitmately try and genocide a group of people with. If you want to kill a bunch of people quick and easy, displace oxygen in the tanks. No unnecessary, messy, hazardous chemicals involved.Llet's not pretend like Germans weren't the world leaders in engineering at the time.

You know, if i were a "nasty nazi" looking for efficiency solutions for my freedom labor camp, I would probably experiment with delousing entire groups of people at one go - so, I would like to know the lethal dosage of this delousing agent so that I can be sure not to exceed it. I don't want to kill off my labor but I do want to kill the lice they carry.

Honestly, the whole gas thing is so stupid and makes no sense. There are much simpler and cheaper ways to kill people. I can't believe people still believe this nonsense.

But you guys are the experts, can you calculate this for us? Or give us even a rough estimate?