A sample of gas occupies 250 mL under laboratory conditions
of27oC and 740 mmHg pressure. What is the volume
atstandard temperature and pressure conditions?

Respuesta :

Answer : The volume at standard temperature and pressure conditions is, 222 mL

Explanation :

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas = 740 mmHg

[tex]P_2[/tex] = final pressure of gas = 760 mmHg

[tex]V_1[/tex] = initial volume of gas = 250 mL

[tex]V_2[/tex] = final volume of gas = ?

[tex]T_1[/tex] = initial temperature of gas = [tex]27^oC=273+27=300K[/tex]

[tex]T_2[/tex] = final temperature of gas = [tex]0^oC=273+0=273K[/tex]

Now put all the given values in the above equation, we get:

[tex]\frac{740mmHg\times 250mL}{300K}=\frac{760mmHg\times V_2}{273K}[/tex]

[tex]V_2=221.5\approx 222mL[/tex]

Therefore, the volume at standard temperature and pressure conditions is, 222 mL