If pressure in a full nitrous oxide “E” cylinder is 745 psi at 20°C, the pressure in a half-full cylinder will be about ______ psi:
Explanation Pressure in a half-full “E” cylinder of nitrous oxide will still be 745 psi. Nitrous oxide is present in the cylinder as a liquid, and therefore, the volume
remaining in the cylinder does not reflect the pressure in the cylinder. Capacity of an “E cylinder” of nitrous is about 1590 L. It is not until three-fourth of the
gas is consumed (about 400 L remaining) that the pressure in the cylinder begins to fall. Therefore, the reliable way to determine the remaining nitrous
oxide in the cylinder is to weigh the cylinder. The empty weight of the cylinder is stamped on the cylinder.
