A sample of O2 gas is placed in a sealed 1.00 L flask and pressure is measured as temperature is changed. The data are plotted and the slope of the resulting line is equal to 0.00500 atm/K. The line passes through the origin of the graph. There are g of O2 gas in the flask.

(R = 0.08206 L*atm/K*mol)

.005/.08206 x 32grams and you get your answer