1. The problem statement, all variables and given/known data A sample containing only NO2 and SO2 has a total pressure of 120 torr. Measurements show that the partial pressure of NO2 is 43 torr. If the vessel has a volume of 800.0 ml and the temperature is 22.0°C, how many moles of each gas are present? 2. Relevant equations PV = nRT 3. The attempt at a solution I tried to solve it using the equation above by solving for n for each gas (using their given pressure). For the n of NO2, I had the answer 3.1 x 10-3 (using n = PV/RT). But the book provides a different answer for it which is 1.9 x 10-3. My question is I would like to know how my answer turned to be incorrect. I don't know any other possible methods of solving this than the ideal gas law. Thank you.