A manufacturer quotes a standard co2 canister contains 16g of co2 at a volume of 20cm^3. So I need to calculate the pressure in the canister.... Using ideal gas law P = nRT/V n = 0.364mol (16 of co2) R = 8.314 J/Kmol (universal gas constant) T = 294k (gas is at room temp 21 deg C) V = 20cm3 (volume of canister as quoted) P = 444 Bar However the manufacturer quotes the canister pressure to be 60Bar! This seems a bit more realistic to me but I've no idea how this could be the case. Any thoughts to clear up the confusion?