Question

The stop cock connecting the two bulbs of volume $5$ litre and $10$ litre containing an ideal gas at $9$ atm and $6$ atm respectively, is opened. What is the final pressure in two bulbs if the temperature remains same?

Answer 1

According to combined gas law

(Refer to Image)

$P_1{V}_1+P_2{V}_2=P(V_1+V_2)$ (at constant temperature)

$\Rightarrow 9\times 5+6\times 10=P\left(15\right)$

$\Rightarrow 45+60=P\left(15\right)$

$P=\frac{105}{15}=7atm$

$P_{final}=7atm$ .

the correct answer is 7atm.