Answer:
85.5 mmHg is the pressure of the gas sample when the valve is opened.
Explanation:
The combined gas equation is,
![\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}](https://tex.z-dn.net/?f=%5Cfrac%7BP_1V_1%7D%7BT_1%7D%3D%5Cfrac%7BP_2V_2%7D%7BT_2%7D)
where,
= initial pressure of gas in container A = 165 mmHg
= final pressure of gas = ?
= initial volume of gas in container A= ![135 mL](https://tex.z-dn.net/?f=135%20mL)
= final volume of gas = 135 mL + 117 mL = 252 mL
= initial temperature of gas in container A = ![22.5^oC=273+22.5=295.5 K](https://tex.z-dn.net/?f=22.5%5EoC%3D273%2B22.5%3D295.5%20K)
= final temperature of gas = ![12.7^oC=273+12.7=285.7K](https://tex.z-dn.net/?f=12.7%5EoC%3D273%2B12.7%3D285.7K)
Now put all the given values in the above equation, we get:
![P_2=\frac{P_1V_1\times T_2}{T_1\times V_2}](https://tex.z-dn.net/?f=P_2%3D%5Cfrac%7BP_1V_1%5Ctimes%20T_2%7D%7BT_1%5Ctimes%20V_2%7D)
![=\frac{165 mmHg\times 135 mL\times 285.7 K}{295.5 K\times 252 mL}](https://tex.z-dn.net/?f=%3D%5Cfrac%7B165%20mmHg%5Ctimes%20135%20mL%5Ctimes%20285.7%20K%7D%7B295.5%20K%5Ctimes%20252%20mL%7D)
![P_2=85.5 mmHg](https://tex.z-dn.net/?f=P_2%3D85.5%20mmHg)
85.5 mmHg is the pressure of the gas sample when the valve is opened.