Question

weather balloon is filled with helium to a volume of 340 L at 30 ∘C and 751 mmHg . The balloon ascends to an altitude where the pressure is 495 mmHg and the temperature is -27 ∘C.What is the volume of the balloon at this altitude?

Answer 1

Answer: Thus the volume of the balloon at this altitude is 419 L

Explanation:

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

The combined gas equation is,

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

where,

$P_1$ = initial pressure of gas = 751 mm Hg

$P_2$ = final pressure of gas = 495 mm Hg

$V_1$ = initial volume of gas = 340 L

$V_2$ = final volume of gas = ?

$T_1$ = initial temperature of gas = $30^oC=273+30=303K$

$T_2$ = final temperature of gas = $-27^oC=273-27=246K$

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

$\frac{751\times 340}{303}=\frac{495\times V_2}{246}$

$V_2=419L$

Thus the volume of the balloon at this altitude is 419 L