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KCHEM
a closed flask contains a 0.25 moles of O2 which exerts a pressure of 0.50 atm. if 0.75 moles of CO2 is added to the container what is the total pressure in the flask
Well you need ideal gas law. So the equation is:\[\frac{ P _{1}V _{1} }{ n _{1}T _{1} }=\frac{ P _{2}V _{2} }{ n _{2}T _{2} } \rightarrow P _{2}=\frac{ P _{1}V _{1}n _{2}T _{2} }{ n _{1}T _{1}V _{2} }\]So if you cancel the Ts and the Vs since the temperature and the volume is equal you get that \[P _{2}=P _{1}\frac{ n _{2} }{ n _{1}} =0.5atm \frac{ 0.75mol }{ 0.25mol }=1.5atm\]