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A closed vessel with rigid walls contains 1 mol of 238 U 92 and 1 mol of air at 298K. Considering complete decay of 238 U 92 to 206 Pb 82, the ratio of the final pressure to the initial pressure of the system at 298 K is?
Although the ans given by IIT is 9, but they have not taken into account the pressure exerted by the air present in the vessel.