Question

A valve separates two tanks, one containing 7.6 liters of oxygen at 4.0 atmospheres and the other containing 4.0 liters of carbon dioxide at 11.0 atm. When the valve is opened and the two gases are allowed to come together, what is final pressure

Answer 1

Answer:

$P_F=6.6atm$

Explanation:

Hello,

In this case one could assume an initial temperature like 0 °C in order to compute both the moles of oxygen and carbon dioxide as shown below:

$n_{O_2}=\frac{PV}{RT}=\frac{4.0atm*7.6L}{0.082\frac{atm*L}{mol*K}273.15K} =1.4mol\\n_{CO_2}=\frac{PV}{RT}=\frac{11.0atm*4.0L}{0.082\frac{atm*L}{mol*K}273.15K}=2.0mol$

Now, the total moles are:

$n_T=1.4mol+2.0mol=3.4mol$

Therefore, the final pressure:

$P_F=\frac{nRT}{V}=\frac{3.4mol*0.082\frac{atm*L}{mol*K}*273.15K}{7.6L+4.0L}\\ P_F=6.6atm$

Best regards.