I chose B from P1V1=P2V2. But A was the correct answer.
The key says it is less than 20L because 200atm (P1) is greater than 10 atm, so the size of the molecules cannot be ignored. 0.1L (V1) is slightly greater than it should be for an ideal gas. Therefore the calculated V2=20: is slightly larger than it should be.
1) So in what case would C be correct? None? In other words, why is it slightly larger and not smaller?
2) when it says V1 is slightly greater than an ideal gas, what is the boundary for this "ideal" volume?
3) If 10 atm (maxima) is the boundary for pressure, is there a minima?->giving a volume larger/smaller?