Five mol of calcium carbide arc combined with 10 mol of water in a closed, rigid, high pressure vessel of 1800 cm3 internal empty volume. Acetylene gas is produced by the reaction:
CaC2(s) + 2H2O(t) ( C2H2(g) + Ca(OH)2(s)
The vessel contains packing with a porosity of 40% to prevent explosive decomposition of the acetylene. Initial conditions are 25(C and l bar, and the reaction goes to completion. The reaction is exothermic, but owing to heat transfer, the final temperature is only 125(C. Determine the final pressure in the vessel,
At 125(C. the molar volume of Ca(OH)2 is 33.0 cm3 mol-1. Ignore the effects of any gases (e.g., air) initially present in the vessel.