Question

Consider the of bulbs shown arrangement below.
If the pressure of the system when all the stop cocks are opened is x (in atm) then find 100 x ? (760 mm = 1 atm)

Answer 1

If T is constant, then the PV is constant (Boyle's law).

$\therefore P_1{V}_1+P_2{V}_2+P_3{V}_3=P_4{V}_4$ ---------(1)
Where $P_4$ is a total pressure and $V_4$ is a total volume.

Now, the total volume of all the container$=V_4=V_1+V_2+V_3=1+1+0.5=2.5L$
Now, putting all the values in equation (1) we get,

$300\times 1+240\times 1+440\times 0.5=X\times 2.5$

$\therefore X=\frac{760}{2.5}=304mm$

Now, 760mm is equivalent to 1atm

$\therefore$ 304mm is equivalent to $\frac{304}{760}=0.4atm$

Thus, x=0.4 atm

$\therefore 100x=40atm$