Under what pressure does a cylinder with a capacity of 80 liters at 27 degrees Celsius contain 1 kg of hydrogen.

Initial data: Т (absolute temperature of hydrogen) = 27 ºС = 300 К; V (cylinder volume) = 80 l = 0.08 m ^ 3; m (mass of hydrogen) = 1 kg.

Reference data: R (universal gas constant) = 8.31 J / (mol * K)); M (molar mass of hydrogen) = 0.002 kg / mol.

We express the hydrogen pressure in the cylinder from the Mendeleev – Clapeyron equation:

P * V = (m / M) * R * T.

P = m * R * T / (M * V).

P = 1 * 8.31 * 300 / (0.002 * 0.08) = 15581250 Pa ≈ 15.6 MPa.

Answer: Hydrogen is in the cylinder under a pressure of 15.6 MPa.