How Do We Calculate the Volume of O2 at STP from Experimental Data?

[starry_eyes]

Data: O2 gas production
Trial 1 Trial 2
Mass of tube and contents prior to O2 production (g) 24.5196 g 24.4328 g
Mass of tube and contents after O2 production (g) 24.4315 g 24.3513 g
Mass of O2 generated (g) 0.0881 g 0.0815 g
Moles of O2 generated (mol) 0.00275 mol 0.00255 mol
Temperature of H2O (C) 23 O C 23 O C
Barometric Pressure (mmHg) 621.5 mmHg 621.5 mmHg
Vapor Pressure of H2O (mmHg) 21.1 mm Hg 21.1 mm Hg
Partial Pressure of O2 (mmHg) 600.4 mm Hg 600.4 mm Hg
Volume of O2 at RT&Pressure 70.5 77.8
Volume of O2 at STP
Volume of 1 mole of O2 at STP
The items in red is what I am having problems with I figured everything else out I just need help getting started on how to find the volume of O2 at STP and the Volume of 1 mole of O2 at STP

 

[Gokul43201]

Use the ideal gas relation in either of the following forms:

\frac {P_1V_1}{T_1} = \frac {P_2V_2}{T_2}

OR

PV = nRT