A student placed a mixture of BaO and CaO in a 1.46L flask containing carbon dioxide at 35C and 746mmHg. After the reactions were complete she found that the CO2 pressure had dropped to 2.40 x 10^2mmHg. How many moles of CO2 were consumed in the reactions? Assume volumes of the solids are negligible.

So far, I know to convert to Kelvin, so T = 308K. P = 0.98atm

2 answers

Initial P = 746 mm Hg.
Final P = 240
delta P = 746-240 = 506 mm Hg.
Change that to atm and use PV = nRT. YOu know P,V, R, and T. Calculate n.
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